N-bromobutanimide → 2,2-dimethyl-2H-1-benzopyran-6-carbonitrile

Participants

Reaction Steps

The compound of the formula (II) is brominated in the benzyl position by N-bromo-succinimide in haloalkanes in the presence of a trace of peroxide and 6-cyano-3,4-dihydro-2,2-dimethyl-4-bromo-2H-1-benzopyran of the formula (X) ##STR12## is almost quantitatively formed and this can be similarly with almost quantitative yield dehydrobrominated with alkali alcoholates to produce 6-cyano-2,2-dimethyl-2H-1-benzopyran of the formula (III).

Provenance & Evidence