| 摘要 |
PURPOSE:To obtain a corresponding aldehyde or alcohol under an extremely mild condition, by reacting a carboxylic acid with a chloroformic ester to give a mixed acid anhydride and reducing the mixed acid anhydride with a metallic boron hydride. CONSTITUTION:A carboxylic acid shown by the formula R<1>COOH (R<1> is 1-20C alkyl, alkenyl, alkynyl or aryl) is reacted with a chloroformic ester shown by the formula ClCOOR<2> (R<2> is 1-20C alkyl, alkenyl, alkynyl or aryl) to give a mixed acid anhydride shown by the formula R<1>COOCOOR<2>, which is dripped to suspension of a metallic boron hydride (e.g. sodium boron hydride or potassium boron hydride) in a solvent such as THF, etc., at -50-30 deg.C to give an aldehyde shown by formula R<1>CHO or an alcohol shown by the formula R<1>CH2 OH. When the aldehyde is preferentially obtained, the amount of the metallic boron hydride is 1.0-1.5 equivalent based on the carboxylic acid and the reaction is carried out at -50-0 deg.C for 2-6hr.
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