o-Hydroxy benzonitrile prepn. from o-hydroxy benzamide - by reaction with phosgene in a non-polar solvent

摘要

The prepn. of o-hydroxybenzonitrile (I) by dehydration of o-hydroxybenzamide (IIe with COCl2 is carried out in a nonpolar solvent at the b. ot of the reaction mixt. (I) is an intermediate for pharmaceuticals, e.g beta-receptor blockers with a 1-(o-nitrilophenoxy)-2-hydroxy-3-alkyl amino structure. The process gives high yields (ca 95%) of high purity (I) from a relatively inexpensive starting material (II). Prefd. solvents are toluene and xylene.