OChem 2 - Exam 3

Grignard/organolithium

Ketones & Aldehydes - require 1 equivalent

Esters & Acid Chlorides - require 2 equivalents

Acid Protons (OH) - require 1 equivalent

Carboxylic Acids (Grignard) - require 1 equivalent and will only deprotonate

Carboxylic Acids (Organolithium) - requires 2 equivalents

Aldehyde

Ester

Carboxylic Acid

Ketone

Imine

Amide

Anhydride

Substitution of Carboxylic Acid with Grignard

Will not undergo substitution, only deprotonation

NaBH4 cannot

Cannot reduce carboxylic acids, only deprotonate

Carboxylic Acid to Acid Chloride

SOCl2

Acid Chloride to Carboxylic Acid

H20, pyridine

Carboxylic acid to first degree alcohol

1.) Excess LiAlH4 2.) H3O+

Acid Chloride to Anhydride

Carboxylic acid and H+

Carboxylic Acid to Anhydride

Acid Chloride, pyridine

Anhydride to Ester

R-OH

Ester to Carboxylic acid

H+, H20

Carboxylic Acid to Ester

R-OH, H+

Ester to Amide

excess R-NH2, Heat

Amide to Carboxylic Acid

[H+], H2O, Heat

Acid Chloride to Ester

R-OH, pydridine

Acid Chloride to Amide

Excess NH3 (2 eq)

Ester to Aldehyde

1.)DIBAL-H, cold -78c

2.)H3O+

Acid Chloride to Aldehyde

1.) LiAl(OtBu)3H

2.)H3O+

1st degree alcohol to Carboxylic Acid

Na2CrO7 (same as CrO3)

H2SO4 / H+, H2O

Ester to 1st degree alcohol

1.) Excess LiAlH4

2.) H3O+

Amide to Amine

1.) Excess LiAlH4

2.) H+, H2O

NaBH4

Reduces aldehydes to primary alcohols

Reduces ketones to secondary alcohols

Doesn’t react with anything less reactive than ketone (Carboxylic acids, amides, Esters)

TBSCl (used with Imidazole or NEt3)

Protective group for hydroxyl and amine groups

TBAF

Gets rid of TBSCl protective group

LiAlH4

Reduces aldehydes to 1st degree alcohols,

ketones to 2nd degree alcohols

esters and carboxylic acids to 1st degree alcohols

Reduces amides and nitriles to amines

Acid Chloride to Aldehyde

LiAlH(OtBu)3

H+ workup

Ester to Aldehyde

DIBAL (1eq)

-78 C

NEt3

strong bulky base

Carboxylic Acid to Amide

DCC

R-NH2

CrO3, pyridine

oxidize primary alcohols to aldehydes,

secondary alcohols to ketones.

When acid is present: primary alcohols and aldehydes are oxidized to carboxylic acids.

KMnO4

primary alcohols and aldehydes to carboxylic acids

secondary alcohols to ketones

Reactivity of Carbonyl Function Groups

Acid Chloride>Anhydride> Aldehyde>Ketone>Ester>Carboxylic Acid>Amide

Acid Chloride to Ketone

CuLiCH4 (2 eq)

Anhydride to amide

NH3 (excess)

Ester to 3rd Degree alcohol

R—MgBr

H+ workup

Ester to 1st degree alcohol

excess LiAlH4

Anhydride to Ester

R—OH

Ketone to 2nd Degree Alcohol

LiAlH4

or

NaBH4

Ketone to 3rd degree alcohol

CrO3, H+, H20

2nd degree alcohol to Ketone

PCC or CrO3, H+, H2O

Acid Chloride to Ketone

(CH3)2 CuLi

Carboxylic Acid to Ketone

CH3Li (2 eq)

R-CN to Ketone

CH3-MgBr (1 eq)

R-CN to Amide

H2O

amide to R-CN

SOCl2

1st degree alcohol to Aldehyde

PCC

Aldehyde to 1st degree Alcohol

LiAlH4

R-CN to Aldehyde

DIBAL (1eq)

Aldehyde to Carboxylic Acid

H3O+

Ester to Carboxylic Acid

H20, H+