Highly atom-economic one-pot formation of three different C-P bonds: general synthesis of acyclic tertiary phosphine sulfides.
The reaction of benzothiadiphosphole 1 with an equimolar mixture of R1MgBr and R2MgBr gave intermediate A', which, after only 4-5 min, was treated with an equimolar amount of R3MgBr, giving the asymmetric phosphine PR1R2R3 in 45% overall yield (75-80% yield when R1 = R2 and 85-90% yield when R1 = R2 = R3) and the byproduct 6 in 90% yield. The treatment of 6 with PCl3 quantitatively regenerates the starting reagent 1. Treatment of the phosphines with elemental sulfur gave the corresponding sulfides.
Baccolini
Graziano
G
Dipartimento di Chimica Organica A. Mangini, Viale Risorgimento, 4, 40136 Bologna, Italy. baccolin@ms.fci.unibo.it
Boga
Carla
C
Mazzacurati
Marzia
M