An easily available Pd(OAc)(2)/(2-mesitylindenyl)dicyclohexylphosphine/Me(octyl)(3)N(+)Cl(-)/K(3)PO(4)·3H(2)O catalytic system was developed and it shows high catalytic activity in the Suzuki-Miyaura cross-coupling reaction of a diverse array of aryl and heteroaryl chlorides in water. Notably, this catalytic system also works with ultra-low loading of the catalyst with high turnover numbers.

A facile asymmetric total synthesis of (+)-aspidospermidine has been developed, which is accomplished in 11 steps in an overall yield of 9.6%. Key steps involve a palladium-catalyzed enantioselective decarboxylative allylation to install the quaternary carbon stereocenter and a highly efficient reductive amination−carbonyl reduction−dehydration−intramolecular conjugate addition cascade to build the cis D-ring.

Thermal treatment of (1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (1) and (3-mesityl-1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (3) with tBuONa followed by [(η(6)-cymene)RuCl(2))](2) in methanol gave the adduct {(η(6)-cymene)RuCl(2)[(1H-inden-3-yl)PCy(2)]} (6) and {(η(6)-cymene)RuCl(2)[(3-mesityl-1H-inden-3-yl)PCy(2)]} (7), respectively. Thermal treatment of (2-phenyl-1H-inden-3-yl)dicyclohexylphosphinium tetrafluoroborate (4) with tBuONa followed by [(η(6)-cymene)RuCl(2))](2) or RuCl(3)·3H(2)O in methanol gave {Ru[κ(P):(η(6)-2-phenyl-1H-inden-3-yl)PCy(2)]Cl(2)} (8). Whereas (2-mesityl-1H-inden-3-yl)dicyclohexylphosphine (5) reacted with [(η(6)-cymene)RuCl(2))](2) (in toluene) or RuCl(3)·3H(2)O (in ethanol) to afford {Ru[κ(P):(η(6)-2-mesityl-1H-inden-3-yl)PCy(2)]Cl(2)} (9). The molecular structures of complexes 6, 8 and 9 have been determined by single-crystal X-ray diffraction analysis. In addition, complexes 8 and 9 have been found to catalyze the acceptorless dehydrogenation of alcohols in toluene. 9 displayed high activity and different substrates, including cyclic and linear alcohols, were efficiently oxidized to ketones by using 2.0 mol% of catalyst.

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