Abstract
While there are several known methods for stereoselectively allylating carbonyls and related compounds, the number of homoallylation reactions, with one more carbon in the chain, is significantly smaller. The bishomoallyl products are more complex than their allylation counterparts, and can potentially add up to three stereocenters in one reaction. Our group previously developed cyclopropylcarbinyl boronates to homoallylate and homocrotylate aldehydes. Here, we modify the cyclopropylcarbinyl boronate for homomethallylation to place a methyl delta to the hydroxyl of the product, and additionally for homomethcrotylation to add methyls in both beta and delta positions. We have obtained some of the desired bishomomethallyl alcohols, and bishomomethcrotyl alcohols in >95% ee, but isomeric byproducts are always observed.