SYNTHESIS OF (ETA-5-C5ME5)RU(ETA-6-TRYPTAMINE)(CF3SO3) COMPLEXES - CHEMOSPECIFIC ETA-6 COORDINATION OF THE (ETA-5-C5ME5)RU+ MOIETY

A series of CpRu(eta6-N(b)-acyltryptamine)OTf and Cp*Ru(eta6-N(b)-CBZ -tryptamine)OTf complexes have been prepared from the reaction of CpR u(CH3CN)3OTf (1) with the corresponding N(b)-acyl-tryptamine and N(b)- CBZ-tryptamine derivatives in THF at ambient reaction conditions under an argon atmosphere. The complexes are air stable and were obtained i n high yields (>90%). CpRu(eta6-N(b)-BOC-tryptamine]OTf (10) and Cp*R u(eta6-N(b)-CBZ-tryptamine)OTf(16) were readily converted into CpRu(e ta6-tryptamine)OTf (3) in good yields (61% and 87%, respectively). The kinetic eta6 coordination of the electrophilic CpRu+ moiety was foun d to be chemospecific for the electron-rich indole nucleus. No competi ng eta6 coordination was observed at the arene unit of a variety of su bstituted N(b)-CBZ-tryptamine derivatives.