Reactions of Grignard Reagents with Carbonyl Compound: Unexpected Observations

Treatment of the ketones 1, 5, 7 with Grignard reagents yielded the products 4, 6, 8, respectively. The ester 9 with Grignard reagent followed by alkaline hydrolysis afforded lactones 10 and 11, respectively. The lactones 14 and 17 on being treated with Grignard reagent furnished the diketone 15 and the chloroketone 18 respectively. The epoxide 19 with Grignard reagent produced diol 21 whereas the epoxide 22 suffered ring contraction yielding the aldehyde 23.