Reactions of Ketones without Chelation Assistance

In 1965, it was reported that refluxing a mixture of RhCl3/PPh3 in cyclohexanone or acetophenone afforded RhCl(CO)(PPh3)2, the CO ligand of which is 

acyclic aryl ketones underwent decarbonylation in the presence of a rhodium complex bearing a bulky cyclopentadienyl hgand (Eq. (6.2)) [4]. 

Catalytic variants of the decarbonylation of unstrained ketones still remain undeveloped, except for the decarbonylation of 1,2- and 1,3-diketones (Eq. (6.3)) [5]. 

Recently, it was reported that a rhodium-catalyzed reaction of benzyl ketone 1 with thioester 2 resulted in scrambling of the acyl groups to yield 3 and 4 (Eq. (6.4)) [6]. A broad range of benzyl ketones undergo this scrambling reaction with thioesters and esters under these conditions. Although the mechanism for this process remains elusive, rhodium-mediated activation of benzylic C-C=0 bonds 

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