COUPLING OF 1,3-DIYNES ON A TRIRUTHENIUM CLUSTER - REACTIONS OF RU-3(MU(3)-PHC2C-CPH)(MU-DPPM)(CO)(8) WITH SIME3C-CC-CSIME3

Reactions between Ru-3(mu(3)-PhC2C=CPh)(mu-dppm)(CO)(8) (1) and SiMe3C =CC=CSiMe3 have given the complexes Ru-2(mu-dppm) {mu-C(C=CPh)=CPhC(Si Me3)=C(C=CSiMe3)} (CO)(4) (3), containing the two diynes coupled in he ad-to-head fashion, Ru-3{mu(3)C(SiMe3)=C(C=CSiMe3)C(=CPh)C(=CPh)C(O)} (mu-dppm)(CO)(7) (4), containing a metalla-indenone ligand formed by c oupling of the two diynes with CO, and 4)-PhC2C=CPh)(mu(4)-SiMe3C2C=CS iMe3)(mu-CO)(CO)(8) (6), in which the two diynes are on opposite sides of a puckered Ru-4 rhomboid. Also formed were thermolysis products of 1, Ru-3{mu(3)-CPhCHCC(C6H4)} (mu-dppm)(CO)(8) (5) (previously describ ed) and Ru-4(mu(4)-PhC2C=CPh)(mu-dppm)(CO)(10) (7), the dppm-substitut ion product of Ru-4(mu(4)-PhC2C=CPh)(CO)(12). The X-ray determined str uctures of 3, 6 and 7 are reported. (C) 1998 Elsevier Science S.A. All rights reserved.