The FeBr₃-Catalyzed Transfer Hydrogenation of Styrene Derivatives under Mild Reaction Conditions

Abstract

The transfer hydrogenation of alkenes was realized by using a simple transition-metal compound (FeBr₃) and 1,4-cyclohexadiene (1,4-CHD) as the hydrogen donor. The conversion of a number of di- and trisubstituted alkenes was investigated, and even a tetrasubstituted alkene was successfully converted. Compared with previously published work with the more expensive InBr₃, the reaction times were considerably reduced and significantly milder reaction conditions could be applied. Interestingly, a transformation that was catalytic in 1,4-CHD, with molecular hydrogen as a stoichiometric reducing agent at 1 bar, was also accomplished.

Key words

addition reaction - alkenes - iron catalysis - hydrogenation - transfer hydrogenation - cyclohexadiene

• References and Notes


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