Synthesis and characterisation of the six-membered cyclopalladated complexes of 2-benzylbenzothiazole

The six-membered cyclopalladated complex di-mu-acetato-bis[2-(2'-thiazolylmethyl)phenyl-C-1,N] dipalladium(II), [{Pd(mu-O(2)CMe)(eta(2)-bbt)}(2)] (eta(2)-bbt=2-(2'-thiazolylmethyl)phenyl-C-1,N),has been prepared by the reaction of palladium(II) acetate and 2-benzylbenzothiazole. Its di-mu-halogeno analogues [{Pd(mu-X)(eta(2)-bbt)}(2)], synthesised by the metathetical reaction with LiCl or NaX, undergo bridge-splitting reactions with some pyridine derivatives and thallium(I) acetylacetonate to yield corresponding mononuclear cyclopalladated complexes. The cyclopalladated feature and the six-membered structure have been confirmed by the H-1 NMR spectra of the mononuclear pyridine complexes, Temperature-dependent H-1 NMR spectra have been observed for [{Pd(mu-O(2)CMe)(eta(2)-bbt)}(2)] and [Pd(acac)(eta(2)-bbt)] and are attributed to inversions of acetato bridges and the boat-formed six-membered ring, respectively.