Diboron complexes of binucleating bis(amidinate) ligands

The synthesis and X-ray crystal structures of the following bis(amidinate)-substituted boron halides are reported: 1,3-C6H4[C{N(SiMe3)}(2)BCl2](2) (3), 1,4-C6H4[C{N(SiMe3)}(2)BCl2](2) (4), 1,4-C6H4[C{N(SiMe3)}(2)B(Ph)Cl](2) (5), 1,4-C6H4[C{NCy}(2)BCl2](2) (6), and 1,4C(6)H(4)[C6H4C{NCy}(2)B(Ph)Cl](2) (7). Compounds 3-5 were prepared by trimethylsilyl chloride elimination, while 6 and 7 were prepared via salt metathesis reactions of the appropriate dilithiurn bis(amidinates) with BCl3 or PhBCl2. The molecular structures of complexes 3, 5, and 6 were determined by single-crystal X-ray diffraction, along with that of the free bis(amidine) 1a. (c) 2006 Elsevier B.V. All rights reserved.