Method for making acylamides by synthesizing and acylating benzoxazines
申请人:——
公开号:US20040044206A1
公开(公告)日:2004-03-04
A method is provided for synthesizing acylamides, useful as protectant for cultivated plants. A benzoxazine, such as 3,4-dihydro-3-methyl-2H-1,4-benzoxazine, is made in a stepwise manner by initially forming an o-nitrophenoxyketone by reacting a haloketone and a nitrophenol. The o-nitrophenoxyketone is hydrogenated to form the corresponding benzoxazine, which is thereafter acylated with an acylhalide to produce the acylamide, such as 4-dichloroacetyl-3,4-dichloroacetyl-3,4-dihydro-3-methyl-2H-1,4-benzoxazine.
A process for preparing acyl amide compounds is described, in which a recrystallized o-nitrophenoxy carbonyl compound is hydrogenated with hydrogen gas in the presence of a nickel sponge metal catalyst with ring closure to form a benzoxazine, which is then reacted with an acyl halide to give the corresponding acyl amide compound.