Highly regioselective sN2'reactions of adducts 6 (readily prepared by reactions of halides with the allyl anion 12 of 11) with Grignard reagents gave enol ethers 13, which were converted (in one-pot reactions from 11) into ketones 14 and a-bromoalkyl ketones 15 in good yields. The monoprotected 1, 4-diketone derivative 16 (prepared by Michael addition of the allyl anion 12 with methyl vinyl ketone) was converted both into l, 4-diketones 18 ...
