Sodium cyanoborohydride unsaturated carbonyl compounds

Asymmetric reduction of a,/ -unsaturated carbonyl compounds using chiral complexes (Section 5.4.1, p. 521) could feasibly lead to optically active allylic alcohols. Other reducing agents which have some merit of regioselectivity, but not stereoselectivity, are sodium cyanoborohydride,244 and sodium boro-hydride in the presence of lanthanide salts.245... [Pg.795]

When the sodium cyanoborohydride reduction of tosylhydrazones discussed on page 150 is applied to a, 8-unsaturated carbonyl compounds, double-bond migration invariably occurs. Suggest a mechanism for this process. [Pg.156]

Sodium triacetoxyborohydride Na[BH(OAc)3] ° and hydrogenation (H2, Pd/C) are used as alternatives to sodium cyanoborohydride for the reductive amination of carbonyl compounds. Also, Zn[BH4]2 is a particularly effective agent for the reductive amination of a,p-unsaturated aldehydes and ketones. ... [Pg.109]