N-Arene complexes

Braga and Grepioni have undertaken a series of analyses of the crystal structures of metal carbonyl clusters, 7t-arene complexes, mixed carbonyl n-arene complexes and some substituted derivatives [170]. Their analyses are based on examination of the packing details and motifs in the crystal structures, recognition of specific interactions, calculation of the packing potential energy for the crystal and consideration of contributions to the lattice volume. Their objective, to investigate the interplay between molecular structure and crystal structure, is very similar to the perspective in this article. 

T -Arene complexes containing late metals have been known for many years, but the scope and utility of these complexes have increased in recent years. Copper(I) and silver form labile arene complexes of various stoichiometries that are apparently T -arene complexes. A few of these complexes have been structurally characterized. More recently, a large number of V-arene and heteroarene complexes of osmium, rhenium, molybdenum, and tungsten have been prepared for the purpose of dearomatization of the arene or heteroarenes. Two examples are shown in Figure 2.33. This dearomatization creates a diene or vinyl unit that imdergoes the organic chemistry of ttiese isolated units, instead of the chemistry of an arene. n -Arene complexes of rhodium and platinum have been characterized structurally and studied in the context of their likely intermediacy in the oxidative addition of arene C-H bonds. ... 

Hydrocarbon-Metal n-Complexes, Other than n-Cyclopentadienyl n-Arene Complexes 327... 

Hydrocarbon-Metal n-Complexes, Other than n-Cyclopentadienyl n-Arene Complexes 339 NMR150. The X-ray crystal structure of [Rh(ti4-COD)Cu(PPh3)(Ti5-7,8-C2B9H9Me)] has been... 

Hydrocarbon-Metal n-Complexes, Other than n-Cyclopentadienyl < n-Arene Complexes 361 The rcaction362 of [Cp Rh(PMe3)(OTf)2] with either [Pt(PPh3)2(il2-C2H4)] or... 

PhCN has an unusually unhindered C—C bond, an intermediate n -arene complex is possible and this may help bring the metal close to the C—C bond. Finally, M—CN is unusually strong for a C—C bond because of the TT-bonding possible with this CO analog. 

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