GaCl3-assisted [3+2] cycloaddition:: A route to new binary PN-heterocycles

Starting from a [3+2] synthetic tool kit, new PN-heterocycles may be isolated according to a new synthetic approach called GaCl3-assisted [3+2] cycloaddition. According to this concept the dipolarophile Mes*-N=P-Cl (Mes* = 2,4,6-tri-tert-butylphenyl) was reacted with the 1,3-dipole (TMS)(2)N-N(TMS)-PCl2 (TMS = trimethylsilyl) yielding the kinetically stabilized [3+2] cycloaddition product triazadiphosphole, Mes*N3P2, stabilized as GaCl3 adduct. Synthesis, structure and bonding are discussed. (C) 2006 Elsevier B.V. All rights reserved.