Green synthesis of 6-cyano-2,2-dimethyl-2-H-1-benzopyran and itssubsequent enantioselective epoxidation

ABSTRACT: tThe clean synthesis of 6-cyano-2,2-dimethyl-2-H-1-benzopyran epoxide starting from 3-methyl-2-butenal is reported using recyclable catalysts. H4PMo11VO40(PMo11V) and (PyH)3HPMo11VO40(Py3–PMo11V) Keggin-type heteropolyacids were used to synthesize 6-cyano-2,2-dimethyl-2-H-1-benzopyran in t...