Practical procedure for the chemoselective reduction of esters by sodium borohydride. Effect of the slow addition of methanol.

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概要

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• The effect of solvents on the reduction of esters was examined with readily available sodium borohydride which is known to be incapable of reducing such functional groups. In mixed solvents of <I>t</I>-butyl alcohol–methanol or tetrahydrofuran–methanol, various carboxylic esters and lactones were found to be reduced by sodium borohydride to the corresponding alcohols or diols in high yields. Slow addition of methanol to the refluxing mixture of ester and sodium borohydride in <I>t</I>-butyl alcohol or tetrahydrofuran was essential to achieve effective reduction. On the other hand, each individual solvent, methanol or <I>t</I>-butyl alcohol, was not effective for the reduction. The procedure provided a practical method for the functional group selective reduction of esters in the presence of chloro, cyano, carboxylato, carbamoyl, carboxy or nitro groups, which can not usually be performed by lithium aluminium hydride.

• 公益社団法人 日本化学会の論文

著者

• Soai Kenso

  Department Of Applied Chemistry Faculty Of Science Science University Of Tokyo

• OYAMADA Hidekazu

  Department of Applied Chemistry, Faculty of Science, Science University of Tokyo(SUT), and CREST, Ja

• Takase Masako

  Department of Applied Chemistry, Faculty of Science, Science University of Tokyo

• Ookawa Atushiro

  Department of Applied Chemistry, Faculty of Science, Science University of Tokyo

• Oyamada Hidekazu

  Department of Applied Chemistry, Faculty of Science, Science University of Tokyo

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