| 摘要 |
Primary and secondary alcohols are prepared by selectively reducing an aldehyde or ketone with a quaternary ammonium borohydride of general formula <FORM:0930706/IV(a)/1> wherein R1, R11, R111, R1111 may be the same or different and are alkyl, aryl, or alkyl-substituted aryl radicals. The borohydrides need not be isolated from their preparation solutions, which may be from the reaction of an aqueous-alcoholic solution of a quaternary ammonium salt or hydroxide with an alkali metal borohydride, and the aldehydes and ketones may be present during the preparation. The process is stereospecific and may be performed in water, alcohols, amines, ethers and amides particularly dimethyl formamide. Examples describe the preparation of trichloroethanol from chloral using tetra-ethyl ammonium borohydride; benzyl alcohol from benzaldehyde using trimethyl-phenyl-ammonium borohydride; p-nitrobenzyl alcohol from p-nitrobenzaldehyde, and threo - 1 - p-nitrophenyl-2-acetamino-propane-1, 3-diol from p-nitro - a - acetamino-b -hydroxy-propiophenone using tetraethyl ammonium borohydride. Specification 795,130 is referred to.
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