Carboxylic acids, reduction prim

NaBH4 is superior to LiAlH4 in selective reductions. In "water or methanol soln., it is an effective reagent for the conversion of aldehydes and ketones to the corresponding alcohols. Aoid chlorides are reduced to prim, alcohols in non-aq. media, but carboxylic acids, anhydrides, esters and nitriles are practically unaffected.—E Cinnamaldehyde —> cinnamyl alcohol. Y 97%.—n-Butyryl chloride —n-butanol Y 81%. (F. e. s. S. W. Chaikin, W. G-. Brown, Am. Soc. 71,122 (1949) s. a. H. Heusser et al., Helv. 33, 1093 (1950).)... 

Alcohols from oxo compds. 20 eqs. NaBH4 added to a soln. of 5 eqs. ZrC in THF at room temp, under N2, a soln. of 4 eqs. acetophenone in the same solvent added, and the mixture stirred at room temp, for 5 h - 1-phenylethanol. Y 96%. ZrCl4 is inexpensive, easy to use, and does not affect ar. nitro compds. and bromides. F.e., also reduction of carboxylic acids, esters and halides to prim, alcohols, and amides, oximes, alkoximes, nitriles, and imines to amines, s. S. Itsuno et al.. Synthesis 1988, 995-6. 

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