Synthesis and coordination properties of 1-tert-butylchlorophosphino- and 1,2-bis(tert-butylchlorophosphino)-1,2-dicarba-closo-dodecaborane(12) -: molecular structures of rac- and meso-1,2-(PtBuCl)2C2B10H10 and (R,R,R,R/S,S,S,S)-[{Cu{1,2-(PtBuCl)2C2B10H10}(μ-Cl)}2]

1-tert-Butylchlorophosphino-1,2-dicarba-closo-dodecaborane(12) (1) and a mixture of stereoisomers of rac- and meso-1,2-bis(tert-butylchlorophosphino)- 1,2-dicarba-closo-dodecaborane(12) (2a, b; 2a:2b = I -. 1) are readily obtained from (BuPCl2)-Bu-t and 1-lithio- and 1,2-dilithio-1,2-dicarba-closo-dodecaborane(12), respectively. The stereoisomers of 2a, b were separated by column chromatography. Compounds I and 2a, b react with [AuCl(tht)] (tht = tetrahydrothiophene) to yield [AuCl(1-(PBuClC2B10H11)-Bu-t)] (3) and [AuCl{1,2-((PBuCl)-Bu-t)(2)C2B10H10}] (4). A mixture of 2a and 2b reacts with CuCl in THF to give (R,R,R,R/S,S,S,S)-[{Cu{1,2-((PBuCl)-Bu-t)(2)C2B10H10} (mu -Cl)}(2)] (5) in 48% yield. Compounds 1-5 were characterised spectroscopically (H-1, P-31, B-11, C-13 NMR; IR), and X-ray structure determinations were carried out on 2a, b and 5. (C) 2001 Published by Elsevier Science Ltd.