| 摘要 |
PURPOSE:To obtain advantageously the titled two functional group-containing compound useful as an intermediate for drugs and industrial chemicals, by condensing a ketone having methylene at alpha-position with an aldehyde or ketone in the presence of stannous trifluoromethanesulfonate. CONSTITUTION:A ketone having methylene at alpha-position shown by the formula I is condensed with an aldehyde or ketone shown by the formula II (R<1>-R<4> are hydrocarbon residue which may contain substituent group, R<1> and R<2>, and R<3> and R<4> may be bonded respectively to form a ring, R<2>-R<4> are further H) in the presence of stannous trifluoromethanesulfonate, to give the desired compound, such as a compound shown by the formula III. By this method, the stannous compound is reacted with the ketone having methylene at alpha-position to form a novel combined substance (stannous enolate), which is easily condensed with the aldehyde or ketone. When the reaction product has stereospecificity, the titled two functional group-containing compound, which is important in terms of chemical synthesis, is obtained in extremely high stereoselectivity. |
