Process for the preparation of symmetrical 2,2-methylenebisbenzotriazolyl phenols

摘要

Compounds of formula <IMAGE> wherein R1 is hydrogen alkyl, alkoxy, phenyl, phenylaklyl or halogen, and R2 is alkyl phenyl, phenylaklyl or cycloalkyl, are prepared by reacting a compound of formula <IMAGE> with a compound of formula <IMAGE> wherein R3 and R4 are alkyl, and formaldehyde, in a one-pot process in the absence of a solvent.