Acid-catalysed Condensation of Phenolic Compounds with Cinnamyl Alcohol. Synthesis of Flavans and Linear Pyranocoumarins

Department of Chemistry, University of Delhi, Delhi-110 007

Manuscript received 4 April 1988, accepted 10 August 1988

Add-catalysed condensation of 2 methylresorcinol (1) with cinnamyi alcohol gave 2-4. The flavan (3) has been used for the synthesis of dihyaropyranocoumarins (5,10 and 14) which on dehydrogenation with DDQ gave the pyranocoumarins (8, 12 and 15,respectively).