| 摘要 |
<p>PURPOSE:A novel method of introducing methyl group into an organic compound, wherein a quarternary ammonium salt of Mannich base is subjected to reductive deamination using sodium cyanoborohydride as a reducing agent. CONSTITUTION:A Mannich base of formula I (R<1> is phenyl having OH group in the 2 or 4-position, naphthyl having OH group in the o-position; R<2>, R<3> are alkyl), such as 2-dimethylamino-4-nitrophenol, is made to react with a compound of the formula: R<4>-X (R<4> is residue that obtained by removing one hydrogen from an organic group), such as dimethyl sulfate, to form the quarternary ammonium salt of formula II, which is subjected to reductive deamination in an aprotic polar solvent using sodium cyanoborohydride as a reducing agent to produce the objective compound of formula III, such as 4-nitro-o-cresol in good yield. EFFECT:Even when the compound bears reducible groups in the molecule, the group is not reduced in the deamination.</p> |
