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Examines the impact of carbenoid-induced carbon (C)-hydrogen (H) on catalytic asymmetric benzylic C-H activation. Reaction mechanism of aryldiazoacetate with ethylbenzene derivatives; Influence of methylene site in the C-H activation; Activation of toluene and isopropylbenzene.

The C-H activation of silyl ethers by means of rhodium carbenoid-induced C-H insertion represents a very direct method for the stereoselective synthesis of silyl-protected β-hydroxy esters. The reaction can proceed with very high regio-, diastereo-, and enantioselectivity and represents a surrogate to the aldol reaction. The reaction is catalyzed by the rhodium prolinate complex Rh[sub 2](S-DOSP)[sub 4]. A critical requirement for the high chemoselectivity is the use of donor/acceptor-substituted carbenoids such as those derived from methyl aryldiazoacetates. A range of silyl ethers may be used such as allyl silyl ethers, tetraalkoxysilanes, and even simple trimethylsilyl alkyl ethers. In general, C-H activation preferentially occurs at methylene sites, as the reactivity is controlled by a delicate balance between steric and electronic effects. [ABSTRACT FROM AUTHOR]

A correction is offered to the article "Small-Molecule Inducer of β Cell Proliferation Identified by High-Throughput Screening," from volume 135, 2013.