Section 6: Reductions

catalytic hydrogenation

Pt, H₂

Heterogenous reductions

Crabtree’s Cat, H₂

how does crabtree’s cat work? where does it add H?

1. acts as a lewis acid, splits H₂ so we have a reactive H, then attaches to lewis base.

2. adds to same face as lewis base

reductions on molecules that rely on double bond as nuc

H₂NNH₂, CuSO_4, O₂

Noyori & others

Red-Al

reduction of carbonyl into amine

RNH₂, AcOH, NaBH₃CN

hint (A_mine A_cid C_{yanoborohydride})

Luche

A: NaBH₄, NiCl₂

B: NaBH₄, CeCl₃

AlH₃

1. BCl₃

2. Bu₄NBH₄

CBS reduction

CBS cat, BH₃SMe₂

birch reduction

Li, NH₃, t-BuOH

Ester and Ether into primary alcohol

1) excess LiAlH₄
2) H3O

aldehyde or ketone into alcohol

a. NaBH₄, MeOH

b. H₂, Pt

c. 1) LiAlH₄, 2)H₃O