Titanocene-catalyzed regioselective alkylation of styrenes with grignard reagents using beta-bromoethyl ethers, thioethers, or amines.
Regioselective double alkylation of styrenes with alkyl Grignard reagents and alkyl bromides having a heteroatom functional group at the beta-position has been achieved by the use of a titanocene catalyst in THF. When ether was used instead of THF as a solvent, monoalkylation by substitution of a vinylic hydrogen atom with an alkyl group proceeded under similar conditions. These reactions involve the addition of alkyl radicals to styrenes to form benzylic radical intermediates.
Terao
Jun
J
Science and Technology Centre for Atoms, Molecules and Ions Control, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 565-0871, Japan. terao@chem.eng.osaka-u.ac.jp
Kato
Yuichiro
Y
Kambe
Nobuaki
N