Abstract Among the active pyrethroid insecticides containing various substituted cyclpropanecarboxylates, esters derived from 2, 2-dimethyl-5, 6-benzospiro [2, 4] heptene-1- carboxylic acid (1) have been 1 found to have particularly high activity, Our continuing interest in the synthesis of novel pyrethroid insecticides2 led us to a study of synthetic methodology for constructing spiro-fused systems such as (1).