kimia organik

of 54 /54
Overview of the Reactions of Carbonyl Compounds • Topical Outline of Coverage – I. Kinds of Carbonyl Compounds. – II.Polarity of the Carbonyl Functional Group. – III.General Reactions of Carbonyl Compounds • A. Nucleophilic Addition Reactions • B. Nucleophilic Substitution Reactions

Author: veronashaq

Post on 02-May-2017

233 views

Category:

Documents


2 download

Embed Size (px)

TRANSCRIPT

  • Overview of the Reactions of Carbonyl CompoundsTopical Outline of CoverageI. Kinds of Carbonyl Compounds.II.Polarity of the Carbonyl Functional Group.III.General Reactions of Carbonyl CompoundsA. Nucleophilic Addition ReactionsB. Nucleophilic Substitution Reactions

  • Kinds of Carbonyl Compounds All carbonyl compounds contain the acyl group

    where the (R) residue bonded to the carbonyl maybe alkyl, aryl, alkenyl, or alkynyl. The different kinds of carbonyl compounds arise from the nature of the other residue bonded to the carbonyl group.

    1.txt$c4d$1481Chemistry-4D-Draw 300Region 0.000 0.000 969.793 -701.850#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS21 2Times New Roman; 12 0 R WIN 0 1 184 2Times New Roman; 7 0 R WIN 0 1 1822#Group 0157.947 -42.297 724.397 -591.8630.000 0.000 0.000 0.0006.30 0#version 210MOL 4 3449.665 -370.851 0.000 1 1 1 C 0 0244.963 -489.035 0.000 2 1 2 C 0 0449.665 -134.482 0.000 3 1 3 O 0 0676.094 -501.578 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 311#Group 0411.250 -326.600 488.750 -424.560419.000 -380.333 0.000 0.00010.00 01 0C41 449.000 -370.000 021#Group 0206.250 -445.600 283.750 -543.560214.000 -499.333 0.000 0.00010.00 01 0R43 244.000 -489.000 031#Group 0405.000 -90.600 495.000 -188.560414.000 -144.333 0.000 0.00010.00 01 0O41 449.000 -134.000 0end14#Group 042.000 -62.940 802.793 -659.85048.303 -69.243 796.490 -653.5476.30 [email protected]@ Chemistry-4D-Draw

  • Kinds of Carbonyl Compounds

    2.txt$c4d$2875Chemistry-4D-Draw 300Region 0.000 0.000 4616.000 -1718.000#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS11 2Times New Roman; 12 0 R WIN 0 1 18112#Group 042.000 -440.400 931.250 -1262.2400.000 0.000 0.000 0.00010.00 0#version 210MOL 4 3482.760 -936.500 0.000 1 1 1 C 0 0158.000 -1124.000 0.000 2 1 2 C 0 0482.760 -561.500 0.000 3 1 3 O 0 0807.519 -1124.000 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 0411.750 -867.400 554.250 -1022.240426.000 -952.333 0.000 0.00010.00 01 0C11 482.000 -936.000 021#Group 094.000 -1055.400 224.000 -1210.240107.000 -1140.333 0.000 0.00010.00 01 0R13 158.000 -1124.000 031#Group 0404.875 -492.400 561.125 -647.240420.500 -577.333 0.000 0.00010.00 01 0O11 482.000 -561.000 041#Group 0736.750 -1055.400 879.250 -1210.240751.000 -1140.333 0.000 0.00010.00 01 0X11 807.000 -1124.000 0end1#Group 01356.000 -136.000 2730.000 -332.0001387.000 -234.000 0.000 0.00010.00 01 0X = H then aldehyde11#Group 01356.000 -332.000 2543.000 -528.0001387.000 -430.000 0.000 0.00010.00 01 0X= R then ketone11#Group 01356.000 -528.000 3240.000 -724.0001387.000 -626.000 0.000 0.00010.00 01 0X = OH then carboxylic acid11#Group 01356.000 -724.000 3001.000 -920.0001387.000 -822.000 0.000 0.00010.00 01 0X = Cl then acid chloride11#Group 01356.000 -920.000 4178.000 -1116.0001387.000 -1018.000 0.000 0.00010.00 01 0X = OR then ester (cyclic esters = lactones)11#Group 01356.000 -1116.000 3438.000 -1312.0001387.000 -1214.000 0.000 0.00010.00 01 0X = OCOR then acid anhydride11#Group 01356.000 -1312.000 4303.000 -1508.0001387.000 -1410.000 0.000 0.00010.00 01 0X = N then amide (cyclic amides = lactams)12#Group 01731.000 -1306.557 1974.739 -1448.0000.000 0.000 0.000 0.00010.00 0#version 210MOL 2 11922.739 -1358.557 0.000 1 1 1 C 0 01783.000 -1396.000 0.000 2 1 2 C 0 02 1 0 0 0#pseudo_bond 0#atom_label 0end2#Group 01700.000 -1417.000 1941.243 -1600.2370.000 0.000 0.000 0.00010.00 0#version 210MOL 2 11889.243 -1548.237 0.000 1 1 1 C 0 01752.000 -1469.000 0.000 2 1 2 C 0 02 1 0 0 0#pseudo_bond 0#atom_label 0end14#Group 01190.000 -42.000 4449.000 -1676.0001200.000 -52.000 4439.000 -1666.00010.00 [email protected]@ Chemistry-4D-Draw

  • Categories of Carbonyl CompoundsCarbonyl Compounds may be grouped into two broad categories based upon whether or not they take part in Nucleophilic Substitution Reactions

  • Aldehydes and KetonesAldehydes and Ketones -X = H and R respectively ; these carbonyl compounds do not undergo nucleophilic substitution reactions. That is to say, the H and R groups are never substituted by other groups. Both H- and R- make poor leaving groups.

    X

    R

    X

    3.txt$c4d$1481Chemistry-4D-Draw 300Region 0.000 0.000 969.793 -701.850#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS21 2Times New Roman; 12 0 R WIN 0 1 184 2Times New Roman; 7 0 R WIN 0 1 1822#Group 0157.947 -42.297 724.397 -591.8630.000 0.000 0.000 0.0006.30 0#version 210MOL 4 3449.665 -370.851 0.000 1 1 1 C 0 0244.963 -489.035 0.000 2 1 2 C 0 0449.665 -134.482 0.000 3 1 3 O 0 0676.094 -501.578 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 311#Group 0411.250 -326.600 488.750 -424.560419.000 -380.333 0.000 0.00010.00 01 0C41 449.000 -370.000 021#Group 0206.250 -445.600 283.750 -543.560214.000 -499.333 0.000 0.00010.00 01 0R43 244.000 -489.000 031#Group 0405.000 -90.600 495.000 -188.560414.000 -144.333 0.000 0.00010.00 01 0O41 449.000 -134.000 0end14#Group 042.000 -62.940 802.793 -659.85048.303 -69.243 796.490 -653.5476.30 [email protected]@ Chemistry-4D-Draw

  • Carboxylic Acids and their DerivativesCarboxylic acids and their derivatives X = some heteroatom (O, Cl, or N). Nucleophilic substitution reactions are possible for these carbonyl compounds because the electronegative heteroatom can stabilize a negative charge and form good Leaving Groups.

    X

    4.txt$c4d$1481Chemistry-4D-Draw 300Region 0.000 0.000 969.793 -701.850#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS21 2Times New Roman; 12 0 R WIN 0 1 184 2Times New Roman; 7 0 R WIN 0 1 1822#Group 0157.947 -42.297 724.397 -591.8630.000 0.000 0.000 0.0006.30 0#version 210MOL 4 3449.665 -370.851 0.000 1 1 1 C 0 0244.963 -489.035 0.000 2 1 2 C 0 0449.665 -134.482 0.000 3 1 3 O 0 0676.094 -501.578 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 311#Group 0411.250 -326.600 488.750 -424.560419.000 -380.333 0.000 0.00010.00 01 0C41 449.000 -370.000 021#Group 0206.250 -445.600 283.750 -543.560214.000 -499.333 0.000 0.00010.00 01 0R43 244.000 -489.000 031#Group 0405.000 -90.600 495.000 -188.560414.000 -144.333 0.000 0.00010.00 01 0O41 449.000 -134.000 0end14#Group 042.000 -62.940 802.793 -659.85048.303 -69.243 796.490 -653.5476.30 [email protected]@ Chemistry-4D-Draw

  • Polarity of the Carbonyl Groups The carbon-oxygen double bond of the carbonyl group is extremely polarized in the direction of the highly electronegative oxygen. This polarization is responsible for the characteristic reactions of carbonyl compounds

    +-

    5.txt$c4d$2444Chemistry-4D-Draw 300Region 0.000 0.000 3572.667 -1240.022#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS21 2Times New Roman; 12 0 R WIN 0 1 185 2Times New Roman; 11 0 R WIN 0 1 1892#Group 042.000 -276.441 846.883 -1022.7960.000 0.000 0.000 0.0009.96 0#version 210MOL 4 3437.155 -764.282 0.000 1 1 1 C 0 0437.156 -390.807 0.000 2 1 3 O 0 0794.923 -970.837 0.000 3 1 4 C 0 093.959 -962.428 0.000 4 1 4 C 0 01 2 2 0 01 3 0 0 01 4 0 0 0#pseudo_bond 0#atom_label 211#Group 0373.000 -702.400 503.000 -841.440386.000 -778.667 0.000 0.00010.00 01 0C51 437.000 -764.000 021#Group 0366.750 -328.400 540.250 -467.440381.000 -404.667 0.000 0.00010.00 01 0O:51 437.000 -390.000 0end1#Group 0313.667 -284.022 406.667 -480.022344.667 -382.022 0.000 0.00010.00 01 0:13#Group 0502.667 -440.022 582.667 -750.022542.667 -725.022 542.668 -465.02210.00 0502.667358 -615.022461582.667358 -615.022461542.667114 -725.0224610.000000 140.000000 30.00000003#Group 0427.435 -42.000 1375.667 -334.0221375.667 -319.022 427.435 -319.01810.00 0550.597168 -233.390869496.588745 -174.373169901.667114 -617.022461560.022400 140.000000 30.000000-13#Group 0429.807 -919.018 1427.667 -1167.6561427.667 -934.022 429.807 -934.01810.00 0565.568604 -999.606689520.155273 -1065.467285928.667114 -473.022461679.633789 140.000000 30.00000011#Group 01323.667 -211.022 3364.667 -407.0221354.667 -309.022 0.000 0.00010.00 01 0nucleophilic oxygen reacts with 11#Group 01313.667 -377.022 3093.667 -573.0221344.667 -475.022 0.000 0.00010.00 01 0acid and other electrophiles11#Group 01396.667 -836.022 3405.667 -1032.0221427.667 -934.022 0.000 0.00010.00 01 0electrophilic carbon reacts with11#Group 01406.667 -1002.022 3259.667 -1198.0221437.667 -1100.022 0.000 0.00010.00 01 0bases and other [email protected]@ Chemistry-4D-Draw

  • General Reactions Of Carbonyl Compounds

    Nucleophilic Addition Reactions

    Nucleophilic Acyl Substitution

  • Nucleophilic Addition Reactions Chapter 09There are two different ways in which a nucleophile can add to a carbonyl compound. Each way leads to a different nucleophilic addition reaction but the mechanisms for both reactions involves the same 1st step.In this step, the nucleophile bonds to the carbonyl carbon and thereby causes a carbon-oxygen bond to break. The carbonyl carbon rehybridizes from sp2 to sp3 and the carbonyl oxygen becomes negatively charged. At this point the tetrahedral intermediate can either be protonated to form an alcohol (NaBH4, LiAlH4, or Grignard Reduction) or a non-bonded e- pair on the nucleophile can be used to form a second bond to the carbonyl carbon. The new bond formation causes expulsion of the carbonyl oxygen as H2O.

  • First Type of Nucleophilic Addition Alcohol Formation Ketones and Aldehydes react with NaBH4, LiAlH4, and Grignard reagents to form alcohols

  • Second Type of Nucleophilic Addition Imine formation - Ketones and Aldehydes react with 1o amines to form imines .

  • Nucleophilic Acyl Substitution Theses reactions do not apply to aldehydes and ketones. These reactions involve the substitution of the nucleophile for the X residue of the carbonyl compound.

    6.txt$c4d$3286Chemistry-4D-Draw 300Region 0.000 0.000 3344.000 -772.840#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS11 2Times New Roman; 12 0 R WIN 0 1 18122#Group 042.000 -42.400 773.250 -691.2400.000 0.000 0.000 0.00010.00 0#version 210MOL 4 3400.094 -409.827 0.000 1 1 1 C 0 0158.000 -549.600 0.000 2 1 2 C 0 0400.095 -163.232 0.000 3 1 3 O 0 0649.618 -553.889 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 0329.750 -340.400 472.250 -495.240344.000 -425.333 0.000 0.00010.00 01 0C11 400.000 -409.000 021#Group 094.000 -480.400 224.000 -635.240107.000 -565.333 0.000 0.00010.00 01 0R13 158.000 -549.000 031#Group 0322.875 -94.400 479.125 -249.240338.500 -179.333 0.000 0.00010.00 01 0O11 400.000 -163.000 041#Group 0578.750 -484.400 721.250 -639.240593.000 -569.333 0.000 0.00010.00 01 0X11 649.000 -553.000 0end14#Group 0433.800 -117.400 528.200 -211.800481.000 -133.600 481.000 -195.60010.00 0514#Group 0260.200 -105.300 367.800 -212.900314.000 -122.600 314.000 -195.60010.00 053#Group 0835.000 -338.600 1494.113 -448.600845.000 -393.600 1484.113 -393.60010.00 01334.112793 -353.5999761334.112793 -433.599976845.000000 -393.5999760.000000 140.000000 30.000000014#Group 0821.200 -187.300 952.800 -318.900887.000 -206.600 887.000 -299.60010.00 051#Group 0898.000 -122.600 1198.000 -345.600929.000 -247.600 0.000 0.00010.00 01 0Nu-1 2 412#Group 01648.000 -81.400 2458.125 -731.2400.000 0.000 0.000 0.00010.00 0#version 210MOL 4 32006.094 -449.027 0.000 1 1 1 C 0 01764.000 -588.800 0.000 2 1 2 C 0 02006.095 -202.432 0.000 3 1 3 O 0 02255.618 -593.089 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 01935.750 -380.400 2078.250 -535.2401950.000 -465.333 0.000 0.00010.00 01 0C11 2006.000 -449.000 021#Group 01700.000 -519.400 1830.000 -674.2401713.000 -604.333 0.000 0.00010.00 01 0R13 1764.000 -588.000 031#Group 01928.875 -133.400 2085.125 -288.2401944.500 -218.333 0.000 0.00010.00 01 0O11 2006.000 -202.000 041#Group 02177.875 -524.400 2406.125 -679.2402193.500 -609.333 0.000 0.00010.00 01 0Nu11 2255.000 -593.000 0end14#Group 02039.800 -156.600 2134.200 -251.0002087.000 -172.800 2087.000 -234.80010.00 0514#Group 01866.200 -144.500 1973.800 -252.1001920.000 -161.800 1920.000 -234.80010.00 051#Group 02596.000 -316.600 2960.000 -512.6002627.000 -414.600 0.000 0.00010.00 01 0+ 114#Group 02878.311 -311.911 3010.689 -444.2892939.000 -331.600 2950.000 -424.60010.00 051#Group 02960.000 -258.600 3177.000 -481.6002991.000 -383.600 0.000 0.00010.00 01 0X-1 1 [email protected]@ Chemistry-4D-Draw

  • Nucleophilic Acyl Substitution

  • Carboxylic Acid Derivatives

    7.txt$c4d$2875Chemistry-4D-Draw 300Region 0.000 0.000 4616.000 -1718.000#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS11 2Times New Roman; 12 0 R WIN 0 1 18112#Group 042.000 -440.400 931.250 -1262.2400.000 0.000 0.000 0.00010.00 0#version 210MOL 4 3482.760 -936.500 0.000 1 1 1 C 0 0158.000 -1124.000 0.000 2 1 2 C 0 0482.760 -561.500 0.000 3 1 3 O 0 0807.519 -1124.000 0.000 4 1 4 C 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 0411.750 -867.400 554.250 -1022.240426.000 -952.333 0.000 0.00010.00 01 0C11 482.000 -936.000 021#Group 094.000 -1055.400 224.000 -1210.240107.000 -1140.333 0.000 0.00010.00 01 0R13 158.000 -1124.000 031#Group 0404.875 -492.400 561.125 -647.240420.500 -577.333 0.000 0.00010.00 01 0O11 482.000 -561.000 041#Group 0736.750 -1055.400 879.250 -1210.240751.000 -1140.333 0.000 0.00010.00 01 0X11 807.000 -1124.000 0end1#Group 01356.000 -136.000 2730.000 -332.0001387.000 -234.000 0.000 0.00010.00 01 0X = H then aldehyde11#Group 01356.000 -332.000 2543.000 -528.0001387.000 -430.000 0.000 0.00010.00 01 0X= R then ketone11#Group 01356.000 -528.000 3240.000 -724.0001387.000 -626.000 0.000 0.00010.00 01 0X = OH then carboxylic acid11#Group 01356.000 -724.000 3001.000 -920.0001387.000 -822.000 0.000 0.00010.00 01 0X = Cl then acid chloride11#Group 01356.000 -920.000 4178.000 -1116.0001387.000 -1018.000 0.000 0.00010.00 01 0X = OR then ester (cyclic esters = lactones)11#Group 01356.000 -1116.000 3438.000 -1312.0001387.000 -1214.000 0.000 0.00010.00 01 0X = OCOR then acid anhydride11#Group 01356.000 -1312.000 4303.000 -1508.0001387.000 -1410.000 0.000 0.00010.00 01 0X = N then amide (cyclic amides = lactams)12#Group 01731.000 -1306.557 1974.739 -1448.0000.000 0.000 0.000 0.00010.00 0#version 210MOL 2 11922.739 -1358.557 0.000 1 1 1 C 0 01783.000 -1396.000 0.000 2 1 2 C 0 02 1 0 0 0#pseudo_bond 0#atom_label 0end2#Group 01700.000 -1417.000 1941.243 -1600.2370.000 0.000 0.000 0.00010.00 0#version 210MOL 2 11889.243 -1548.237 0.000 1 1 1 C 0 01752.000 -1469.000 0.000 2 1 2 C 0 02 1 0 0 0#pseudo_bond 0#atom_label 0end14#Group 01190.000 -42.000 4449.000 -1676.0001200.000 -52.000 4439.000 -1666.00010.00 [email protected]@ Chemistry-4D-Draw

  • Carboxylic Acid Derivatives

    These all have an acyl group bonded to Y, an electronegative atom or leaving groupIncludes: Y = halide (acid halides), acyloxy (anhydrides), alkoxy (esters), amine (amides).

  • General Reaction PatternNucleophilic acyl substitution

  • Nucleophilic Acyl Substitution-The MechanismCarboxylic acid derivatives have an acyl carbon bonded to an electronegative group Y that can leaveA tetrahedral intermediate is formed, then the leaving group is expelled to generate a new carbonyl compound, leading to substitution

  • Substitution in SynthesisWe can readily convert a more reactive acid derivative into a less reactive oneReactions in the opposite sense are possible but require more complex approaches

  • Reactions of Acid HalidesNucleophilic acyl substitutionHalogen replaced by OH, by OR, or by NH2Reduction yields a primary alcoholGrignard reagent yields a tertiary alcohol

  • Reactions of Acid AnhydridesSimilar to acid chlorides in reactivity

  • Reactions of EstersLess reactive toward nucleophiles than are acid chlorides or anhydridesCyclic esters are called lactones and react similarly to acyclic esters

  • Chapter 09. Aldehydes and Ketones: Nucleophilic Addition Reactions

    *

  • AldehydesAldehydes are carbonyl compounds having at least one hydrogen attached to the carbonyl carbon.

    8.txt$c4d$3513Chemistry-4D-Draw 300Region 0.000 0.000 4857.250 -1371.600#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS21 2Times New Roman; 12 0 R WIN 0 1 187 2Times New Roman; 9 0 R WIN 0 1 1861#Group 0190.250 -1029.600 804.250 -1225.600221.250 -1127.600 0.000 0.00010.00 01 0propanal12#Group 042.750 -376.400 1154.250 -977.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 4 3915.123 -815.357 0.000 1 1 1 C 0 0540.123 -815.357 0.000 2 1 2 C 0 0165.123 -815.357 0.000 3 1 3 C 0 0915.123 -497.561 0.000 4 1 4 O 0 02 1 0 0 03 2 0 0 04 1 2 0 0#pseudo_bond 0#atom_label 411#Group 0844.750 -746.400 1102.250 -901.240859.000 -831.333 0.000 0.00010.00 01 0CH11 915.000 -815.000 021#Group 0469.750 -750.300 789.250 -925.680484.000 -833.500 0.000 0.00010.00 01 0CH21 2 811 540.000 -815.000 031#Group 094.750 -750.300 414.250 -925.680109.000 -833.500 0.000 0.00010.00 01 0CH31 2 811 165.000 -815.000 141#Group 0837.875 -428.400 994.125 -583.240853.500 -513.333 0.000 0.00010.00 01 0O11 915.000 -497.000 0end1#Group 01919.250 -1101.600 2856.250 -1297.6001950.250 -1199.600 0.000 0.00010.00 01 0Benzaldehyde12#Group 01917.997 -215.571 2968.954 -802.2960.000 0.000 0.000 0.0006.83 0#version 210MOL 9 92464.678 -546.023 0.000 1 1 1 C 0 02350.972 -309.895 0.000 2 1 2 C 0 02094.874 -309.895 0.000 3 1 3 C 0 01966.826 -531.681 0.000 4 1 4 C 0 02094.874 -753.467 0.000 5 1 5 C 0 02350.972 -753.467 0.000 6 1 6 C 0 02671.609 -541.754 0.000 7 1 7 C 0 02799.655 -319.965 0.000 8 1 8 O 0 02861.814 -644.709 0.000 9 1 9 H 0 02 1 2 0 03 2 0 0 04 3 2 0 05 4 0 0 06 5 2 0 06 1 0 0 07 1 0 0 08 7 2 0 07 9 0 0 0#pseudo_bond 0#atom_label 371#Group 02620.125 -486.400 2723.875 -609.6402630.500 -554.000 0.000 0.00010.00 01 0C71 2671.000 -541.000 081#Group 02741.875 -264.400 2858.125 -387.6402753.500 -332.000 0.000 0.00010.00 01 0O71 2799.000 -319.000 091#Group 02803.875 -589.400 2920.125 -712.6402815.500 -657.000 0.000 0.00010.00 01 0H71 2861.000 -644.000 0end1#Group 03774.250 -1133.600 4690.250 -1329.6003805.250 -1231.600 0.000 0.00010.00 01 0formaldehyde12#Group 03910.750 -42.400 4684.250 -858.2400.000 0.000 0.000 0.00010.00 0#version 210MOL 4 34289.506 -538.164 0.000 1 1 1 C 0 04289.506 -163.164 0.000 2 1 2 O 0 04033.720 -720.950 0.000 3 1 3 H 0 04560.116 -694.400 0.000 4 1 4 H 0 02 1 2 0 01 3 0 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 04218.750 -469.400 4361.250 -624.2404233.000 -554.333 0.000 0.00010.00 01 0C11 4289.000 -538.000 021#Group 04211.875 -94.400 4368.125 -249.2404227.500 -179.333 0.000 0.00010.00 01 0O11 4289.000 -163.000 031#Group 03962.750 -651.400 4105.250 -806.2403977.000 -736.333 0.000 0.00010.00 01 0H13 4033.000 -720.000 041#Group 04489.750 -625.400 4632.250 -780.2404504.000 -710.333 0.000 0.00010.00 01 0H11 4560.000 -694.000 [email protected]@ Chemistry-4D-Draw

  • KetonesKetones are carbonyl compounds having two alkyl fragments attached to the carbonyl carbon.

    9.txt$c4d$3633Chemistry-4D-Draw 300Region 0.000 0.000 4644.635 -1389.489#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS31 2Times New Roman; 12 0 R WIN 0 1 185 2Times New Roman; 11 0 R WIN 0 1 187 2Times New Roman; 9 0 R WIN 0 1 1861#Group 0135.250 -1130.489 1019.250 -1326.489166.250 -1228.489 0.000 0.00010.00 01 02-propanone12#Group 041.750 -343.400 1170.250 -1001.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 4 3869.750 -839.689 0.000 1 1 1 C 0 0607.250 -839.689 0.000 2 1 2 C 0 0164.750 -839.689 0.000 3 1 3 C 0 0607.250 -464.689 0.000 4 1 4 O 0 02 1 0 0 03 2 0 0 04 2 2 0 0#pseudo_bond 0#atom_label 411#Group 0798.750 -774.300 1118.250 -949.680813.000 -857.500 0.000 0.00010.00 01 0CH31 2 811 869.000 -839.000 021#Group 0536.750 -770.400 679.250 -925.240551.000 -855.333 0.000 0.00010.00 01 0C11 607.000 -839.000 031#Group 093.750 -774.300 413.250 -949.680108.000 -857.500 0.000 0.00010.00 01 0CH31 2 811 164.000 -839.000 141#Group 0529.875 -395.400 686.125 -550.240545.500 -480.333 0.000 0.00010.00 01 0O11 607.000 -464.000 0end1#Group 01646.250 -1151.489 2583.250 -1347.4891677.250 -1249.489 0.000 0.00010.00 01 0acetophenone12#Group 01635.067 -41.511 2972.764 -1036.8470.000 0.000 0.000 0.0007.89 0#version 210MOL 9 92197.345 -543.214 0.000 1 1 1 C 0 02197.345 -839.043 0.000 2 1 2 C 0 01941.149 -986.958 0.000 3 1 3 C 0 01684.956 -839.043 0.000 4 1 4 C 0 01684.956 -543.214 0.000 5 1 5 C 0 01941.149 -395.302 0.000 6 1 6 C 0 02494.354 -442.428 0.000 7 1 7 C 0 02724.913 -659.906 0.000 8 1 8 C 0 02494.354 -146.601 0.000 9 1 9 O 0 02 1 2 0 03 2 0 0 04 3 2 0 05 4 0 0 06 5 2 0 06 1 0 0 07 1 0 0 08 7 0 0 09 7 2 0 0#pseudo_bond 0#atom_label 281#Group 02673.125 -607.550 2922.875 -747.3802683.500 -673.750 0.000 0.00010.00 01 0CH37 2 871 2724.000 -659.000 091#Group 02436.875 -91.400 2553.125 -214.6402448.500 -159.000 0.000 0.00010.00 01 0O71 2494.000 -146.000 0end1#Group 03375.250 -1140.489 4155.250 -1336.4893406.250 -1238.489 0.000 0.00010.00 01 02-butanone12#Group 03113.865 -515.015 4477.385 -1089.6650.000 0.000 0.000 0.0009.38 0#version 210MOL 5 43421.164 -927.007 0.000 1 1 1 C 0 03629.939 -927.007 0.000 2 1 2 C 0 03832.717 -927.007 0.000 3 1 3 C 0 04184.652 -927.007 0.000 4 1 4 C 0 03629.939 -628.757 0.000 5 1 5 O 0 02 1 0 0 03 2 0 0 04 3 0 0 05 2 2 0 0#pseudo_bond 0#atom_label 511#Group 03165.250 -870.800 3460.750 -1038.2803173.000 -944.667 0.000 0.00010.00 01 0CH35 2 853 3421.000 -927.000 021#Group 03565.000 -865.400 3695.000 -1004.4403578.000 -941.667 0.000 0.00010.00 01 0C51 3629.000 -927.000 031#Group 03768.000 -870.800 4074.000 -1038.2803781.000 -944.667 0.000 0.00010.00 01 0CH25 2 851 3832.000 -927.000 041#Group 04120.000 -870.800 4426.000 -1038.2804133.000 -944.667 0.000 0.00010.00 01 0CH35 2 851 4184.000 -927.000 151#Group 03558.750 -566.400 3701.250 -705.4403573.000 -642.667 0.000 0.00010.00 01 0O51 3629.000 -628.000 [email protected]@ Chemistry-4D-Draw

  • Naming Aldehydes and KetonesAldehydes are named by replacing the terminal -e of the corresponding alkane name with alThe parent chain must contain the CHO group The CHO carbon is numbered as C1If the CHO group is attached to a ring, use the suffix carbaldehyde

  • Names of more Complex Aldehydes

  • Naming KetonesReplace the terminal -e of the alkane name with oneParent chain is the longest one that contains the ketone groupNumbering begins at the end nearer the carbonyl carbon

  • Ketones with Common NamesIUPAC retains well-used but unsystematic names for a few ketones

  • Preparation of Aldehydes and KetonesPreparing AldehydesWe have already discussed two of the best methods of aldehyde synthesis. These are oxidation of primary alcohols, and oxidative cleavage of alkenes. Oxidize primary alcohols using pyridinium chlorochromate

  • Preparing KetonesKetones may be prepared by the oxidation of secondary alcohols. A wide range of oxidizing can accomplish this purpose. Some of these are: Jones reagent (CrO3 in aqueous sulfuric acid), sodium chromate (Na2CrO4) and potassium permanganate (KMnO4).

    10.txt$c4d$2983Chemistry-4D-Draw 300Region 0.000 0.000 4812.000 -2255.600#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS11 2Times New Roman; 12 0 R WIN 0 1 1881#Group 042.000 -1756.600 1635.000 -1952.60073.000 -1854.600 0.000 0.00010.00 01 04-tert-butylcyclohexanol12#Group 0408.000 -41.400 1365.250 -1772.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 8 8784.760 -485.800 0.000 1 1 1 C 0 01109.519 -673.300 0.000 2 1 2 C 0 01109.519 -1048.300 0.000 3 1 3 C 0 0784.760 -1235.800 0.000 4 1 4 C 0 0460.000 -1048.300 0.000 5 1 5 C 0 0460.000 -673.300 0.000 6 1 6 C 0 0784.760 -162.800 0.000 7 1 7 O 0 0784.760 -1610.800 0.000 8 1 8 C 0 02 1 0 0 03 2 0 0 04 3 0 0 05 4 0 0 06 5 0 0 06 1 0 0 07 1 0 0 08 4 0 0 0#pseudo_bond 0#atom_label 271#Group 0706.875 -93.400 977.125 -248.240722.500 -178.333 0.000 0.00010.00 01 0OH11 784.000 -162.000 081#Group 0713.750 -1545.300 1313.250 -1720.680728.000 -1628.500 0.000 0.00010.00 01 0C(CH3)31 4 81 5 1 6 811 784.000 -1610.000 0end1#Group 01688.000 -614.600 2362.000 -836.6001719.000 -712.600 0.000 0.00010.00 01 0Na2CrO41 2 81 3 1 6 813#Group 01626.000 -809.600 2606.409 -919.6001636.000 -864.600 2596.409 -864.60010.00 02446.408691 -824.5999762446.408691 -904.5999761636.000000 -864.5999760.000000 140.000000 30.00000001#Group 01700.000 -901.600 2428.000 -1097.6001731.000 -999.600 0.000 0.00010.00 01 0acetic acid11#Group 02938.000 -1766.600 4645.000 -1962.6002969.000 -1864.600 0.000 0.00010.00 01 04-tert-butylcyclohexanone12#Group 03354.000 -115.400 4311.250 -1824.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 8 83730.760 -538.000 0.000 1 1 1 C 0 04055.519 -725.500 0.000 2 1 2 C 0 04055.519 -1100.500 0.000 3 1 3 C 0 03730.760 -1288.000 0.000 4 1 4 C 0 03406.000 -1100.500 0.000 5 1 5 C 0 03406.000 -725.500 0.000 6 1 6 C 0 03730.760 -236.000 0.000 7 1 7 O 0 03730.760 -1663.000 0.000 8 1 8 C 0 02 1 0 0 03 2 0 0 04 3 0 0 05 4 0 0 06 5 0 0 06 1 0 0 07 1 2 0 08 4 0 0 0#pseudo_bond 0#atom_label 271#Group 03652.875 -167.400 3809.125 -322.2403668.500 -252.333 0.000 0.00010.00 01 0O11 3730.000 -236.000 081#Group 03659.750 -1597.300 4259.250 -1772.6803674.000 -1680.500 0.000 0.00010.00 01 0C(CH3)31 4 81 5 1 6 811 3730.000 -1662.000 0end1#Group 03480.000 -2017.600 3948.000 -2213.6003511.000 -2116.100 0.000 0.00010.00 01 0(90%)[email protected]@ Chemistry-4D-Draw

  • Prep. Of Ketones by Ozonolysis of AlkenesOzonolysis of alkenes yields ketones if one of the doubly bonded carbons is itself bonded to two alkyl groups.

  • Prep. Of Ketones by Hydration of Terminal AlkynesMethyl ketones can be prepared by the Markovnikov addition of water to a terminal alkyne. The reaction needs to be catalyzed by Hg+2 ion. See Section 4.13 of text.

  • Aryl Ketones by AcylationFriedelCrafts acylation of an aromatic ring with an acid chloride in the presence of AlCl3 catalyst (see Section 5.6)

  • Oxidation of Aldehydes and KetonesAldehydes are readily oxidized to carboxylic acid but ketones are unreactive towards oxidation except under the most vigorous conditions. This difference in reactivity towards oxidation lies in the structural difference between the two types of carbonyl compounds. Aldehydes are more easily oxidized because they posses a hydrogen atom bonded to the carbonyl carbon. This hydrogen atom can be removed as a proton with the final result being the oxidation (loss of hydrogen) from the original aldehyde. Ketones have no expendable carbonyl-hydrogen bond.

  • Oxidation of Aldehydes and KetonesMany oxidizing agents will convert aldehydes to carboxylic acids. Some of these are Jones reagent, hot nitric acid and KMnO4.

    One drawback to the Jones reagent is that it is acidic. Many sensitive aldehydes would undergo acid - catalyzed decomposition before oxidation if Jones reagent was used

    11.txt$c4d$2615Chemistry-4D-Draw 300Region 0.000 0.000 4044.875 -713.280#START SETTINGS#Name=Document#DefaultTextFont=Times New Roman; 12 0 R WIN 0 1 18#DefaultLabelFont=Times New Roman; 12 0 R WIN 0 1 18#CurrentColor=0,0,0#BackgroundColor=255,255,255#LineWidth=10.000000#BondLength=375.000000#PaintBrush=1#DashedLineInterval=0.028500#ArrowHeadLength=0.140000#ArrowHeadWidth=0.030000#ArrowHeadFixed=0#ArrowSpaceFixed=0#ArrowSpace=0.050000#ArrowSpaceRatio=0.050000#DoubleBondMinSpace=25.000000#DoubleBondSpaceLengthRatio=0.150000#BoldBondSpaceRatio=0.150000#WedgeBondSpaceRatio=0.666667#HashBondSpaceRatio=0.500000#HashSpace=0.050000#END SETTINGS11 2Times New Roman; 12 0 R WIN 0 1 1842#Group 041.250 -43.400 1526.250 -670.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 4 31112.980 -508.800 0.000 1 1 1 C 0 0817.750 -508.800 0.000 2 1 2 C 0 01112.981 -164.789 0.000 3 1 3 O 0 01402.650 -507.800 0.000 4 1 4 H 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 01041.750 -439.400 1184.250 -594.2401056.000 -524.333 0.000 0.00010.00 01 0C11 1112.000 -508.000 021#Group 093.250 -443.300 856.750 -618.680101.000 -526.500 0.000 0.00010.00 01 0CH3(CH2)41 2 81 3 1 6 81 7 1 8 813 817.000 -508.000 031#Group 01034.875 -95.400 1191.125 -250.2401050.500 -180.333 0.000 0.00010.00 01 0O11 1112.000 -164.000 041#Group 01331.750 -438.400 1474.250 -593.2401346.000 -523.333 0.000 0.00010.00 01 0H11 1402.000 -507.000 0end3#Group 01650.750 -464.800 2243.855 -574.8001660.750 -519.800 2233.855 -519.80010.00 02083.854980 -479.8002932083.854980 -559.8002931660.750000 -519.8002930.000000 140.000000 30.00000002#Group 02272.250 -41.400 3878.125 -669.6800.000 0.000 0.000 0.00010.00 0#version 210MOL 4 33343.980 -507.000 0.000 1 1 1 C 0 03048.750 -507.000 0.000 2 1 2 C 0 03343.981 -162.989 0.000 3 1 3 O 0 03633.650 -506.000 0.000 4 1 4 O 0 02 1 0 0 01 3 2 0 01 4 0 0 0#pseudo_bond 0#atom_label 411#Group 03272.750 -438.400 3415.250 -593.2403287.000 -523.333 0.000 0.00010.00 01 0C11 3343.000 -507.000 021#Group 02324.250 -442.300 3087.750 -617.6802332.000 -525.500 0.000 0.00010.00 01 0CH3(CH2)41 2 81 3 1 6 81 7 1 8 813 3048.000 -507.000 031#Group 03265.875 -93.400 3422.125 -248.2403281.500 -178.333 0.000 0.00010.00 01 0O11 3343.000 -162.000 041#Group 03555.875 -437.400 3826.125 -592.2403571.500 -522.333 0.000 0.00010.00 01 0OH11 3633.000 -506.000 0end1#Group 01628.750 -321.600 2044.750 -517.6001659.750 -419.600 0.000 0.00010.00 01 [email protected]@ Chemistry-4D-Draw

  • A Milder Oxidizing AgentFor acid sensitive molecules a milder oxidizing agent such as the silver ion (Ag+) may be used. A dilute ammonia solution of silver oxide, Ag2O, (Tollens reagent) oxidizes aldehydes in high yield without harming carbon-carbon double bonds or other functional groups.

  • Note; In this reaction the oxidizing agent is Ag+ and it is ultimately reduced to Ag(s).A shiny mirror of metallic silver is deposited on the inside walls of the flask during a Tollens oxidation: observation of such a mirror forms the basis of an old qualitative test for the presence of an aldehyde functional group in a molecule of unknown structure.

    Tollens Oxidation

  • Nucleophilic Addition Reactions of Aldehydes and KetonesNu- approaches 45 to the plane of C=O and adds to the Carbonyl Carbon A tetrahedral alkoxide ion intermediate is produced and ultimately protonated

  • NucleophilesNucleophiles can be negatively charged ( : Nu) or neutral ( : Nu-H)If neutral, the nucleophile usually carries a hydrogen atom that can subsequently be eliminated and carry away the positive charge.

  • Relative Reactivity of Aldehydes and KetonesAldehydes are generally much more reactive than ketones. There are two reasons for this; Aldehydes are less sterically hindered than ketones. In other words the carbonyl carbon of aldehydes is more accessibly to attack. The presence of two relatively large substituents in ketone hinders the attacking nucleophile from reaching the carbonyl carbon.

    The + on the carbonyl carbon is reduced in ketones because of the ability of the extra alkyl group to stabilize a + charge. This ability is emphasized in the stability order of carbocations. 3o>2o>1o

  • Aldehydes Have A Greater Electrophilicity Than Do KetonesAldehyde C=O is more polarized than ketone C=OAs in carbocations, more alkyl groups stabilize + characterKetone has more alkyl groups, stabilizing the C=O carbon inductively

  • Addition of H-Y to C=OReaction of C=O with H-Y, where Y is electronegative, gives an addition product (adduct) and the reaction is readily reversible because the electronegative Y is a good leaving group.

  • Nucleophilic Addition of Alcohols: Acetal FormationTwo equivalents of ROH in the presence of an acid catalyst add to C=O to yield acetals, R2C(OR)2Alcohols, ROH, fall under the category of Y-H and therefore the reaction is reversible.

  • Mechanism for Formation of Acetals

  • Uses of AcetalsAcetals can serve as protecting groups for aldehydes and ketones-remember the rxn. is reversible.It is convenient to use a diol, to form a cyclic acetal (the reaction goes even more readily)

  • Nucleophilic Addition of Grignard Reagents and Hydride Reagents: Alcohol FormationTreatment of aldehydes or ketones with Grignard reagents yields an alcohol Nucleophilic addition of the equivalent of a carbon anion, or carbanion. A carbonmagnesium bond is strongly polarized in the direction of the carbon atom, so a Grignard reagent reacts for all practical purposes as R: and MgX +.

  • Mechanism of Addition of Grignard ReagentsR- attacks the carbonyl carbon. The alkoxide anion is then protonated by dilute acid.Grignard additions are irreversible because a carbanion is not a leaving group

  • Hydride AdditionH- attacks the carbonyl carbon. The alkoxide anion is then protonated by dilute acid.Hydride additions are irreversible because a hydride is not a good leaving groupLiAlH4 and NaBH4 react as donors of hydride ion (H-)

  • Nucleophilic Addition of Amines: Imine FormationPrimary amines (RNH2) add to C=O to form imines, R2C=NR (after loss of HOH)

  • Mechanism of Imine Formation

  • Imine DerivativesAddition of amines that have an adjacent atom containing a lone pair of electrons occurs very readily, giving useful, stable iminesFor example, hydroxylamine forms oximes and 2,4-dinitrophenylhydrazine readily forms 2,4-dinitrophenylhydrazones These are usually solids and help in characterizing liquid ketones or aldehydes by melting points

  • Spectroscopy of Aldehydes and KetonesInfrared SpectroscopyAldehydes and ketones show a strong C=O peak 1660 to 1770 cm1aldehydes show two characteristic CH absorptions in the 2720 to 2820 cm1 range.

  • C=O Peak Position in the IR SpectrumThe precise position of the peak reveals the exact nature of the carbonyl group

  • SummaryAldehydes are from oxidative cleavage of alkenes or oxidation of 1 alcoholsKetones are from oxidative cleavage of alkenes or oxidation of 2 alcohols.Aldehydes and ketones are reduced to yield 1 and 2 alcohols , respectivelyGrignard reagents also gives alcohols 1 amines add to form iminesAlcohols add to yield acetals

    *