Method of preparing aryl triazolinones with trialkyl orthoacetates
申请人:FMC Corporation
公开号:US05449784A1
公开(公告)日:1995-09-12
A method for preparing an alkoxyethylidene-substituted aryl hydrazine having the formula ##STR1## and thereafter cyclizing the same with a cyanate salt under mildly acidic conditions in the presence of an organic solvent, optionally in the presence of a cyclization-aiding amount of water, to form an aryl triazolinone of the formula ##STR2## wherein X is independently hydrogen, halogen, lower alkyl, lower alkoxy, nitro, hydroxy, --NHSO.sub.2 R.sup.1, --NR.sup.1 SO.sub.2 R.sup.1, or --N(SO.sub.2 R.sup.1).sub.2, where R.sup.1 is lower alkyl; R is lower alkyl, and each R is the same; and n is an integer of from 1-3, which triazolinones are useful as intermediates for preparing herbicides.