Nucleophilic additions to polarized vinylarenes

Article abstract of DOI:10.1016/j.tetlet.2016.06.033

The addition of nucleophiles to the terminal double bond carbon of a styrene incorporating an electron-withdrawing group at the ortho or para position has been studied. The conditions for this transformation have been optimized and structural modifications to the substrate have been explored. The structural changes included variation of the activating group on the aromatic ring and positioning substituents on the side chain double bond. The study revealed that nitro substitution gave the best results for addition of carbon and nitrogen nucleophiles. Cyano-substituted systems added carbon nucleophiles, but underwent polymerization or degradation with nitrogen nucleophiles. Ethoxycarbonyl-bearing substrates reacted primarily at the ester carbonyl. The reaction generally proceeded well with methyl on the α carbon of the double bond, but was slowed by methyl at the β position. The yields varied from 50% to 97% for 22 examples.