C–H Activation with Iridium(III) and Rhodium(III) Alkyl Complexes Containing a 2,2′-Bipyridyl Ligand

✍ Scribed by Xiao-Yi Yi; Ka-Wang Chan; Enrique Kwang Huang; Yiu-Keung Sau; Ian D. Williams; Wa-Hung Leung

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 427 KB
• Volume: 2010
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.201000041

✦ Synopsis

Abstract

Heating [Rh(dtbpy)(κ~2~‐C,C′‐CH~2~CMe~2~C~6~H~4~)(CH~2~CMe~2~Ph)] (1; dtbpy = 4,4′‐di‐tert‐butyl‐2,2′‐bipyridyl) in p‐xylene at 110 °C resulted in the formation of the 2‐tert‐butylphenyl complex [Rh(dtbpy)(κ~2~‐C,C′‐CH~2~CMe~2~C~6~H~4~)(C~6~H~4~__t__Bu‐2)] (3). Treatment of complex 1 with diethyl phosphite gave the phosphito‐bridged dimer [Rh(dtbpy)(κ~2~‐C,C′‐CH~2~CMe~2~C~6~H~4~){P(O)(OEt)~2~}]~2~ (4). Refluxing [Ir(dtbpy)(κ~2~‐C,C′‐CH~2~CMe~2~C~6~H~4~)(C~6~H~4~__t__Bu‐2)] (2) with 2‐phenylpyridine (ppyH) and 4‐(2‐pyridyl)benzaldehyde in toluene followed by column chromatography afforded [Ir(dtbpy)(CH~2~CMe~2~Ph)Cl(κ~2~‐N,C‐ppy)] (5) and the carbonyl complex [Ir(dtbpy)(CH~2~CMe~2~Ph)(CO)(R)] (6) [R = 4‐(2‐pyridyl)phenyl], respectively. Anion metathesis of [M(dtbpy)(CH~2~CMe~2~Ph)(H~2~O)(OTs)~2~] with NaBAr^F^~4~ [Ar^F^ = 3,5‐(CF~3~)~2~C~6~H~3~] afforded cationic [M(dtbpy)(CH~2~CMe~2~Ph)(H~2~O)(μ‐OTs)]~2~[BAr^F^~4~]~2~ [M = Rh (7), Ir (8)] that are capable of catalyzing H/D exchange of tetrahydrofuran by using D~2~O as the deuterium source. The crystal structures of complexes 4–7 were determined.