Organic II Mechanisms 1. Alkadienes a. HX addition to a conjugated diene:

b. General Diels-alder cycloaddition reaction(Diene must be in cis configuration):

2. Aromatics a. Electrophilic aromatic substitution (halogenation):

b. Electrophilic aromatic substitution (Nitration):

c. Electrophilic aromatic substitution (Sulfonation):

d. Electrophilic aromatic substitution (Alkylation):

e. Electrophilic aromatic substitution (Acylation):

f. Nucleophilic substitution reaction of aryl halides with EWG (Meisenheimer complex; ortho/para only):

g. Preparation of phenol from halobenzene via benzyne:

3. Alcohols a. 3o alcohol- acid catalyzed dehydration:

b. 2o, 3o alcohol dehydration with POCl3:

c. 3o alcohol to alkyl halide using HX (X= Cl, Br, I):

d. 1o, 2o alcohol to alkyl halide using SOCl2:

e. 1o, 2o alcohol to alkyl halide using PBr3:

4. Ethers a. Acid catalyzed synthesis of symmetrical ethers (1o alcohols only):

b. Williamson ether synthesis (1o or 2o R’X only; can be intramolecular):

c. Alkoxymercuration of alkene to form ethers:

d. Acidic cleavage of ethers(1o and 2o ethers; HI or HBr only):

e. Claisen rearrangement of an allyl aryl:

f. Alkenes with peroxyacid:

g. Alkene with X2/H2O and a strong base:

h. Acid-catalyzed epoxide ring opening(X=F, Br, Cl or I):

i. Base-catalyzed epoxide ring opening (Sn2) :

5. Aldehydes/Ketones a. Nucleophilic addition to a ketone or aldehyde:

b. Grignard(RMgX) addition to a ketone or aldehyde:

c. Hydride addition to a ketone or aldehyde:

d. 1o amine addition to a ketone or aldehyde (Imine formation):

e. 2o amine addition to a ketone or aldehyde (Enamine formation):

f. Wittig Reaction:

g. Conjugate addition of a nucleophile to an α,β-unsaturated aldehyde or ketone:

Nu=RNH2, R2NH, R2CuLi(R:-), -:CN

α

enolate

6. Carboxylic Acids/Nitriles a. Carboxylation of Grignard reagent to prepare carboxylic acids:

b. Nitrile with an organometallic reagent:

7. Carboxylic Acid Derivatives a. Conversion of carboxylic acid into acid chloride:

b. Conversion of carboxylic acid into acid anhydride:

c. Conversion of carboxylic acid into an ester ( 2 ways):

Sn2 Route

Fischer esterification

d. Conversion of carboxylic acid halides into carboxylic acids, esters, amides, aldehydes, ketones, or alcohols: (Y= Cl, Br)

e. Conversion of carboxylic acid anhydrides into carboxylic acids, esters, amides, or alcohols: (Y= O2CR)

f. Conversion of esters into carboxylic acids, amides, or alcohols: (Y= OR)

g. Conversion of amides into carboxylic acids: (Y= NH2, NHR, NR2)

8. Carbonyl α-Substitutions a. Base catalyzed enolate formation:

b. Acid catalyzed enol formation:

c. α-halogenation of a carbonyl (aldehydes/ketones only):

d. Hell-Vollhard-Zelinski (HVZ) reaction (carboxylic acids only):

e. Haloform reaction (methyl ketones only):

f. Alkylation of enolates, esters and ketones (Sn2 reactions):

g. alkylation of nitriles:

h. Malonic ester synthesis:

i. Acetoacetic ester synthesis:

9. Carbonyl Condensations a. General carbonyl condensation reaction:

b. Base catalyzed dehydration of an aldol:

c. Acid catalyzed dehydration of an aldol:

d. Intramolecular aldol condensation reaction:

e. Claisen condensation reaction:

f. Dieckmann cyclization (intramolecular Claisen condensation):

g. Michael addition reactions:

h. Stork enamine reaction:

Reverse of enamine formation yields:

i. Robinson annulation reaction (Combination of Michael rxn 1st, followed by an intramolecular Aldol rxn):

See intramolecular aldol rxn above for the mechanism of part 2.

10. Amines a. Azide synthesis of a primary amine:

b. Gabriel synthesis of an amine:

c. Reductive amination of aldehydes and ketones: