Alcohol and Phenol Reactions

Reducing an aldehyde to a PRIMARY alcohol

H₂/Pd (everything is reduced) or NaBH₄/CH₃OH

Reducing a ketone to a SECONDARY alcohol

NaBH₄/CH₃OH

NaBH₄/H₃O⁺ or CH₃OH

Aldehyde to primary alcohol AND ketone to secondary alcohol

Reducing an aldehyde to a SECONDARY alcohol

1) CH₃MgBr 2) H₃O⁺

Reducing an ketone to a TERTIARY alcohol

1) CH₃MgBr 2) H₃O⁺

1) CH₃MgBr 2) H₃O⁺

Aldehyde to secondary alcohol AND ketone to tertiary alcohol

Reducing a carboxylic acid to a PRIMARY alcohol

1) Excess LiAlH₄ 2)H₃O⁺. Solvent = THF or Et₂O

Reducing an ester to a PRIMARY alcohol

1) Excess LiAlH₄ 2)H₃O⁺. Solvent = THF or Et₂O

1) Excess LiAlH₄ 2)H₃O⁺. Solvent = THF or Et₂O

Reducing a carboxylic acid or ester to a primary alcohol

Grignard reaction of ester with 1) Excess CH₃MgBr 2) H₃O⁺

Reacts twice, with OCH₃ as leaving group

Reaction of carboxylic acid with Grignard reagents

Does NOT react, forms carboxylate salt

Limitations of Grignard reagents

No acidic or electrophilic functional groups

Conversion of alcohols to alkyl halides (SN1 or SN2)

3º alcohol + HX via SN1 and 1º + HX via SN2

Conversion of 1º or 2º to alkyl halides (SN2)

Form good leaving group: tosylate + pyridine, SOCl₂ + pyridine, PBr₃

Alcohol to alkene

1º, 2º or 3º alcohol + conc. H₂SO₄ + heat OR POCl₃ + pyridine @ 0ºC

Oxidation of PRIMARY alcohol

PCC or DMP = aldehyde vs. CrO₃/H₃O⁺ OR KMnO₄/aq. NaOH = carboxylic acid

Oxidation of SECONDARY alcohol

PCC/DMP, CrO₃/H₃O⁺ OR KMnO₄/aq. NaOH = ketone

Oxidation of TERTIARY alcohol

No reaction

PCC or DMP

1º alcohol = aldehyde, 2º alcohol = ketone, 3º alcohol = no reaction

CrO₃/H₃O⁺ OR KMnO₄/aq. NaOH

1º alcohol = carboxylic acid, 2º alcohol = ketone, 3º alcohol = no reaction