Reaktionen der Hydrazid‐verbrückten Cluster HRu 3 (CO) 9 (RN—NR 2 ) mit Alkinen

Reactions of the Hydrazide‐Bridged Clusters HRu 3 (CO) 9 (RN—NR 2 ) with Alkynes The clusters HRu 3 (CO) 9 (RN—NR 2 ) ( 1 ) with triply bridging hydrazide ligands (RN—NR 2 = MeN—NHMe, HN—NHMe, HN—NMe 2 ) undergo reactions with the alkynes HCCPh and PhCCPh to yield three cluster products in each case. One of them ( 2 ) is presumed to result from Ru—H insertion with concomitant cluster opening. The second ( 3 ) contains an open Ru 3 cluster bridged by a unique μ 3 ‐η 2 ‐vinyl ligand, as shown by a structure determination. The third ( 4 ) represents the expected simple reaction product with a s̀,‐bound vinyl ligand, again proved by a structure determination. Cluster type 3 is converted to cluster type 2 by CO addition.