Cluster chemistry: LXXXIII. Reactions of Ru 5(μ 5-C 2PPh 2)(μ-PPh 2)(CO) 13 with olefins: Products formed by addition of an alkene to the C 2 fragment. X-ray structures of Ru 5(μ 4-PPh){μ14-C 2(CHCHR)CHCH 2R}(μ-PPh 2)-(CO) 12 (R = H, Me) and RU 5(μ 4-PPh) (μ -PPh 2) (μ-CO)(CO) 10-{μ 5-C 5H 3Me-1-(CHCH 2)-3}

Abstract

Addition of two molecules of ethene to the C 2PPh 2 unit of Ru 5S(μ 5-C 2PPh 2)(μ-PPh 2)(CO) 13 ( 1) produced two isomers of Ru 5(μ 4-PPh)(μ 4-C 2(CHCH 2)CHMe) (μ-PPh 2XCO) 12 ( 4a, 4b). The metal core consists of a wing-tip-bridged butterfly, one Ru 4 face of which is capped by carbon atom of a hydrocarbon ligand formed by addition of two molecules of ethene to one carbon of a C 2 unit derived from the C 2PPh 2 ligand. The other Ru 4 face is capped by a μ 4-PPh group. The isomers differ in the relative locations of the μ-PPh 2 and CO groups. Reactions with propene and but-l-ene yielded the analogous complexes Ru 5(μ 4-PPh)(μ 4-C 2(CHCHR)CHCH 2R)(μ-PPh 2)(CO) 12 [R = Me ( 5a, 5b), Et ( 6a, 6b)] l. Reaction of 4a with further ethene produced Ru 5(μ 4-PPh)(μz-PPh 2)(μ-CO) (CO) 10 {η 5-C 5H 3Me-1-(CHCH 2)-3} ( 8), in which a square pyramidal Ru 5 core is capped on the square face by a μ 4-PPh ligand. One basal edge is bridged by the μ-PPh 2 group and one of the other basal Ru atoms carries the disubstituted cyclopentadienyl ligand, which has been formed by combination of the third ethene molecule with the μ 4-C 2(CHCH 2)CHMe ligand of 4. Complexes 4a, 5b and 8 were characterised by single-crystal X-ray studies.