SYNTHESIS AND DESIGN OF NOVEL TETRANUCLEAR AND DINUCLEAR GOLD(I) PHOSPHINE ACETYLIDE COMPLEXES - FIRST X-RAY CRYSTAL-STRUCTURES OF A TETRANUCLEAR ([AU-4(TPPB)(C-CPH)(4)]) AND A RELATED DINUCLEAR ([AU-2(DPPB)(C-CPH)(2)]) COMPLEX

Reaction of [Au(C=CR)](infinity) with dppb and tppb in CH2Cl2 afforded the corresponding luminescent Au-2(dppb)(C=CR)(2) and Au-4(tppb)(C=CR )(4) (dppb = 1,4-bis(diphenylphosphino)benzene; tppb = 1,2,4, 5-tetrak is(diphenylphosphino)benzene; R = C6H13, Ph, 4-MeO-Ph); their photophy sical properties have been studied, and the X-ray crystal structures o f Au-2(dppb)(C=CP)(2) (2) and Au-4(tppb)(C=CPh)(4) (5) have been deter mined. Close Au ... Au contacts are present in 5, which twisted the si x-membered ring that comprises the PAu2PC2 unit. Such a structure is r eminiscent of a distorted anthracene-like unit containing Au atoms as part of the heterocycle, owing to the auriophilicity which brings the Au atoms into close contact.