Synthesis and reactivity of poly(pyrazol-1-yl)borate derivatives of cyclopalladation systems, including structural studies of Pd{2-CH2C6H4P(o-tolyl)(2)-C,P}{(pz)(3)BH-N,N '} and Pd(C6H4C5H4N-C-2,N '){(pz)(3)BH-N,N '}

The cyclopalladated complexes Pd{2-CH2C6H4P(o-tol)2}{(pz) nBH4-n} and Pd(C6H4C5H4N-C 2,N′){(pz)nBH4-n} [n=2, 3; pz=pyrazol-1-yl] have been synthesised from the corresponding halide bridged cyclometallated dimers; the crystal structures of the complexes for which n=3 have been determined. The complexes Pd{2-CH2C6H4P(o-tol)2}{(pz) nBH4-n} (n=2, 3) and [Pd{2-CH2C6H4P(o-tol)2}(μ-O 2CMe)]2 are unreactive towards oxidation by alkyl halides, iodobenzene and 4-bromoanisole.