Rhodium catalysis decarbonylation

Ammonia N-donor Ligands Asymmetric Synthesis by Homogeneous Catalysis Decarbonylation Catalysis Hydride Complexes of the Transition Metals Hydroboration Catalysis Hydrogenation Isomerization of Alkenes Hydrosilation Catalysis P-donor Ligands Rhodium Organometallic Chemistry. 

A related approach involves the direct decarbonylation of stable ketones. DauguUs and Brookhart demonstrated that the rhodium-catalyzed decarbonylation of diaryl ketones was feasible [11]. Efficient extrusion of CO from alkyl aryl ketones to form alkylarenes was easily achieved by rhodium(I) catalysis directed by apyridyl ortho to the RCO group (Scheme 22.6) [12]. (CO)2Rh(acac) was found to be the optimal catalyst and the methodology had a broad substrate scope. This method offers an alternative way to synthesize alkyl benzenes through an ARCIS reaction, complementary to the known Friedel-Crafts alkylation reaction of arenes. 

Carbon monoxide insertion and decarbonylation reactions of rhodium complexes have been studied mainly in the context of investigations concerned with catalysis. 

The cychzation of pent-4-enals and related compounds to cyclopentanones is catalyzed by [RhCl(PPh3)3] in a reaction that involves oxidative addition of the -CHO group to the rhodium(I) catalyst. This reaction has much in common with the decarbonylation that most aldehydes undergo in the presence of this catalyst (see Decarbonylation Catalysis). 

Yang, L., Guo, X., Li, C.-J. (2010). The first decarbonylative coupling of aldehydes and norbwnenes catalyzed by rhodium. Advanced Synthesis and Catalysis, 352, 2899-2904. 

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