Free-Radical Reactions of Trialkylboranes with β-Nitrostyrenes To Generate Alkenes

beta-Nitrostyrenes 1 react with trialkylboranes under a nitrogen atmosphere to generate high yields of alkenes 2. The mechanism is proposed to be a free-radical reaction via NO(2)/alkyl substitution since the reaction is stimulated by the presence of a trace of oxygen in the nitrogen or tert-butyl peroxide or by photolysis and is retarded or inhibited by the addition of galvinoxyl to the solution.