Ring expansion reactions of isoquinoline derivatives to 2-benzazocine and 3-benzazecine derivatives
Abstract
Reaction of 2-methyl-1-vinyl-1,2-dihydro- and 1,2,3,4-tetrahydroisoquinolines with dimethyl acetylenedicarboxylate gives 1 : 1 adducts, which are 2-benzazocine and 3-benzazecine diesters, respectively.