alcohol reactions

Primary Alcohol with Hydrogen Halide (H-X)

The OH gets protonated as LG and follows SN2 mechanism with H2SO4

Secondary and Tertiary Alcohol with Hydrogen Halide (H-X)

Follows SN1 mechanism and is faster because of resonance stabilization

Primary and secondary Alcohol reactions with SOCl2 and PBr3

OH gets protonated as a LG and follows SN2 mechanism with ether

Conversion of Alcohol into a Sulfonate Ester (good LG)

Alcohol with MsCl (CH3-SO2Cl) or p-TosCl/Pyridine turns it into good LG to undergo SN2 mechanism (inversion)

Dehydration of Alcohols w/ H3O+, THF

Alcohol undergoes E1 mechanism to form alkene

Dehydration of Alcohols w/ POCl3/Pyridine

Alcohol undergoes an E2 mechanism to form alkene

Oxidation of primary alcohol

produces an aldehyde

Oxidation of an aldehyde

produces a carboxylic acid

oxidation of a secondary alcohol

produces a ketone

Oxidation of a tertiary alcohol

produces no reaction

Example of mild oxidants and their product

• PCC gives an aldehyde from alcohol

• Dess-Martin gives an aldehyde or ketone

Example of strong oxidants and products

KMnO4 and H2CrO4 produce carboxylic acids from alcohol

Substitution with alkyl halide

• primary R-X with strong base (NaOH) → primary alcohol

• tertiary R-X with weak base (H2O) → tertiary alcohol

Reduction of Carbonyl

carbonyl with NaBH4 or LiAlH4/H3O+ → alcohol

Addition with alkene

Hydration: H3O+ → markovnikov alcohol

Hydroboration: (1. BH3 THF 2. H2O2, NaOH) → anti-markovnikov alcohol

Halohydration: (X2/H2O) → markovnikov alcohol with X

Grignard reagent with carbonyl compound

R-X + Mg → R-MgX (Grignard reagent)

carbonyl with

1. RMgX, ether

2. H3O+

→ alcohol + HOMgX