modern organic synthesis mr. anand s burange, institute of chemical technology, matunga,...
DESCRIPTION
WHAT IS A CHEMICAL REACTION? Chemical reaction is an effective interaction between two or more molecules/atoms /ions leading to the formation of new compound(s). 3TRANSCRIPT
MODERN ORGANIC SYNTHESISMODERN ORGANIC SYNTHESISMr. Anand S Burange,Institute Of Chemical Technology, Matunga , Mumbai-400019E-mail: [email protected]
O
OHHO
OH
O
OOH
HO OHO
OOH
OH
OH
O
OO
OH
OH
HO
OOH
OHHO
O
OOH
HO
HO
O
HO
O
HO
H
N
Sir, Robert Boyle ; First man who independently started working in scientific field of chemicals now termed as Chemistry.
In 1828, when F. Wohler accidently got urea in the laboratory, from that day Organic Chemistry came into an existence
2NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
WHAT IS A CHEMICAL REACTION?WHAT IS A CHEMICAL REACTION?
Chemical reaction is an effective interaction between two or more molecules/atoms /ions leading to the formation of new compound(s).
A B
3NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon,
Mumbai
SynthesisOrganic synthesis is a construction of complex organic compounds by a series of chemical reactions.
There are two main areas of research in the field of organic synthesis, namely total synthesis and methodology.
HO
H
H
H
4NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
Three main keys in organic synthesis
OHO
O
HO
H
N
H
O
H
O
5NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
Functional group InterconversionsFunctional group Interconversions
O
O
O
OH
O
O
O
i
ii
iii
iv
v
vi
vii
I. (CH3 )2S+CH2- (DMSO,NaH,Me3S+ )
II. NaBH4/ EtOH
III. Zn-Hg/ HCl OR N2H4 / KOH
IV. SeO2
V. (a) NaBH4/ EtOH (b) H+ /Heat
VI. NaOH
VII. LDA, PhSeBr/H2O2
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i
ii
iii
iv
v
vi
vii
CHO
CH2OH
COOH
O
OH
O
OH
CHO
NO2
i. NaOH (Cannizaro) OR H- donor reductant
ii. K2Cr2O7/H+ OR KMnO4/H+
iii. CH2N2 OR (a) KMnO4/H+ (b) 2eq. MeLi
iv. (a) KMnO4/H+ (b) SOCl2 (c) EtMgBr
v. RhCl(Pph3)3 : Wilkinson’s catalyst
vi. NaCN/EtOH
vii. Conc. HNO3/Conc. H2SO4
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
i
ii
iii
iv
v
vi
vii
O
OH
O
O
O
O
OH
i. CH2I2, Zn(Cu)/ Et2O
ii. m-CPBA (Bartlett Mechanism)
iii. SeO2
iv. (a) SeO2 (b) MnO2
v. (a) SeO2 (b) MnO2 (c) -CH2 –SOMe2
vi. (a) SeO2 (b) MnO2 (c)H2O2/OH-
vii. (a) HBr (b) Mg /Dry ether (C) Ph-CHO
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
i
ii
iii
iv
v
vi
vii
O
O
O
O
CHO
OH
HO
O
CO2Et
NH
O
i. m-CPBA
ii. CH2N2
iii. (a) Cl-CH2-COOEt/Me3CONa (b) H3O+ OR Ph3P=CH-OMe
iv. (a)Mg-Hg/ TiCl4 (b) H2O
v. (a) H2N-OH (b) H+
vi. (a)Pyrrolidine/TsOH (b) CO (OEt)2
vii. Ph3P=CH2
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Some Functional group Interconversions for practiceSome Functional group Interconversions for practice
HO HO
i. 9-BBNii. Ethanolamine
OHNH2 i. Cl-PO(OEt)2/NaH
ii. NaNH2/NH3 (Via Benzyne)
OH
OH
i. Hg(OAc)2 /H2Oii. NaBH4/ OH-
i. B2H6/ solventii. H2O2/ OH-
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
Asymmetric SynthesisAsymmetric Synthesis
OH
OH
OH
OH
OsO4 OR KMnO4
I2/AgOAc (dry) OR (a)m-CPBA (b) Hydrolysis
Alkene dihydroxylation
O
O
NaBH4
NaBH4
CeCl3
OH
OH
Reduction
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
Luche’s Reduction
CO2Me
CO2Me
Stereospecific cycloaddition reactions
CO2Me
CO2Me
MeO2C
CO2Me
CO2Me
CO2Me
[4+2] cycloaddition reactions takes place in presence of heat
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O O
Epoxidation
m-CPBAi. NBSii. OH-
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GETTING SLEEPYNOW IT’S TIME TO MOVE YOUR HEAD UP & DOWN
!!ANTI PERIPLANAR RELATIONSHIP!!
iPr
Cl
MeRO-
?
iPr
Cl
Me
H
iPr
Cl
Me
HRO-
iPr Me
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
OH
TsO(CH3)3O-
NH2OH
HNO2
OH
NH2
HNO2
NH2OH
HNO2
O
CHO
O
O
DON’T GET FRUSTRATED!!!
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
Retrosynthesis – thinking backwards from relatively complex molecules to simpler ones – the disconnection approach originated by E.J. Corey (Nobel Prize 1990)
Terms involvedTarget Molecule (TM) The compound we wish to prepare
Retrosynthetic Analysis The process of WORKING BACKWARDS from the TM in order to devise a suitable synthetic route.
Readily Available Starting Materials (RASM) cheap, commercially available compounds.
Synthon An idealised fragment, usually a cation or anion, resulting from a disconnection.
Synthetic Equivalent The actual compounds used to function as synthons.
Functional Group Interconversion (FGI) The process of writing one functional group for another to help synthetic planning and to help
disconnection.
NET/SET guidance lecture under UGC merged scheme at Patkar College, Goregaon, Mumbai
O
Target MoleculeO
C-C dix O
Synthons
OO
Cl+ AlCl3 Friedel Craft's reagent
Chemical Equivalents (C.E.) O
Cl+ AlCl3
O
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NR2
NO2O2N
CF3
NR2
NO2O2N
CF3
C-N dix
Cl
NO2O2N
CF3
C-N dix
Cl
CF3
TM (Target Molecule)
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Cl
CF3
1. Conc.HNO3/conc.H2SO42. R2NH/Base
NR2
NO2O2N
CF3
Disconnections of Ethers and SulphidesOMe
MeTM
Me
O MeC-O dix
O-methlylation
O
Me
Me+
Synthesis
Me
OH(MeO)2SO2
NaOH
OMe
Me
Cl
S
Cl
C-S dix
Cl
S Cl
Cl
S
Cl
TM
Cl
S
Cl
SH
ClCl
Cl
Cl
SH Cl
Cl+ NaOEt/EtOH TM
Synthesis
C.E.
O
CO2H
TM
O
CO2HC-C dix
O
H2CCO2H
+
O
+ CH2(COOEt)2EtO-/EtOH
O
COOEt
COOEt
O
COOEt
COOEt
1. KOH
2. H+/Heat
O
COOEt
