Dehydrohalogenation by a Germylene:  Conversion of Carbene Ligands into Carbynes at Ruthenium

Abstract

The dialkylgermylene [Ge(CH[SiMe 3 ] 2 ) 2 ] ( 3 ) converts the carbene complexes [Ru(CHR)(PCy 3 ) 2 Cl 2 ] (R = p -C 6 H 4 Me [ 2 ], n -C 4 H 9 [ 6 ]) into the corresponding square-planar carbyne complexes [Ru(CR)(PCy 3 ) 2 Cl] (R = p -C 6 H 4 Me [ 1 ], n-C 4 H 9 [ 7 ]) cleanly within minutes at 25 °C in benzene; addition of HCl to a benzene solution of 1 results in quantitative re-formation of 2 . Replacement of chloride in 1 affords other halide and pseudohalide complexes, [Ru(C- p -C 6 H 4 Me)(PCy 3 ) 2 X] (X = p -OC 6 H 4 - t -Bu, Br, F, O 3 SCF 3 ), cleanly.