| 摘要 |
PURPOSE:To industrially and advantageously obtain the titled compound useful as medicines, agricultural chemicals, etc., selectively without requiring purifica tion of raw materials, by reacting a reaction product of a keto amide with a primary amine with a reaction product of ketene with acetone as the raw materials while heating. CONSTITUTION:A compound expressed by formula I (R<1> is aryl, heterocyclic group, cycloalkyl or secondary or tertiary lower alkyl; R<3> is CH3 or phenyl) is condensed with a compound expressed by formula II (R<2> is H, aryl, heterocy clic group, 1-4C alkyl, lower alkenyl, lower alkynyl, cycloalkyl, etc.; n is an integer 1-4) in an inert solvent through dehyration to give a crude reaction solution of a compound expressed by formula III, which is then reacted with a crude reaction solution of a compound expressed by formula IV (R<4> and R<5> are 1-4C alkyl) obtained by reacting a mixture of diketene with acetone at <=100 deg.C, etc., in an inert solvent, e.g. toluene, at 110-140 deg.C to afford the aimed compound expressed by formula V. Ketones formed as a by-product are reused for producing the compound expressed by formula III. |
