Chloro:phenyl di:methyl pentenone prepn. - by reacting melt of chloro:benzaldehyde with mixt. of di:methyl:butanone, aq. sodium cpd. and methanol

摘要

Prepn. of 1-(4-chlorophenyl) - 4, 4-di-methyl-pent- ene-3-one (I) comprises reacting a melt of 4-chlorobenzaldehyde with a mixt. of 3,3-dimethyl-butane -2-one, an aq. sodium cpd. and methanol at 60 - 70 deg.C. The mixt. is thinned with more methanol and brought to a temp. of 5 - 15 deg.C by evacuation and cooling. The resulting crystalline prod. is washed with methanol and dried. USE/ADVANTAGE - As an intermediate for the fungicide 1-(4-chlorophenyl) -3-(1, 2, 4-triazole-1-yl-methyl) -4, 44-dimethyl-pentane-3-ol. (see EP0040345). The method for prepn. of (I) gives high yields and uses readily-obtainable starting materials. It does not produce ecologically unacceptable waste, since the methanolic wash soln. can be recycled.