Palladium-Assisted Formation of Carbon−Carbon Bonds. 5.¹ Reactions of (<i>o</i>-Styrylaryl)palladium Complexes with Alkynes. Synthesis of Palladium Complexes with Highly Functionalized Indenyl Ligands. Crystal and Molecular Structures of (1-Benzyl-2,3-diphenyl-5,6,7-trimethoxyindenyl)- and (1-Benzyl-3-phenyl-5,6,7-trimethoxyindenyl)palladium(II) Complexes

Abstract

The reactions of [Pd( E -R)Cl(tmeda)] [R = C 6 H( E -CH CHPh)-6-(OMe) 3 -2,3,4; tmeda = N, N, N ‘, N ‘-tetramethylethylenediamine] with Tl(CF 3 SO 3 ) and CH⋮CH, PhC⋮CPh, or PhC⋮CH selectively give compounds [Pd(η-Ind)(tmeda)]CF 3 SO 3 [Ind = 1-benzyl-5,6,7-trimethoxyindenyl ( 2 ), 1-benzyl-2,3-diphenyl-5,6,7-trimethoxyindenyl ( 3 ), 1-benzyl-3-phenyl-5,6,7-trimethoxyindenyl ( 4 )]. When a mixture of [Pd( E -R)Cl(bipy)] (bipy = 2,2‘-bipyridine) and [Pd( Z -R)Cl(bipy)] is reacted with Tl(CF 3 SO 3 ) and MeC⋮CMe, the complex [Pd(η-Ind)(bipy)]CF 3 SO 3 [1-benzyl-2,3-dimethyl-5,6,7-trimethoxyindenyl ( 5 )] is obtained. The structures of 3 and 4 have been determined by X-ray studies at 203 and 173 K, respectively. According to the structural data for 3 and 4, the hapticity of the indenyl ligands is intermediate between η 3 - and η 5 -coordination.