As a subset of C−H functionalization reactions, processes that functionalize the allylic or propargylic positions of alkenes and alkynes are powerful, especially in an enantioselective and diastereoselective manner. We describe methods utilizing Ir/phosphoramidite system which enable the synthesis of 1,5-dienes and 1,5-enynes with high stereoselectivity from C−H functionalization of readily available alkene and alkyne starting materials. We first report a dual catalyst strategy employing iron and iridium catalysts that allows for the direct cross-coupling of <b>alkenes</b> and allylic ethers. Two distinct organometallic intermediates interact synergistically to afford enantioenriched 1,5-dienes. We then also report a stereoselective coupling of <b>alkynes</b> and allylic ethers employing only an iridium catalyst. The coupling products are formed with excellent regio-, diastereo-, and enantioselectivities, and the protocol is functional group tolerant. Mechanistic studies that led to the proposal of a novel catalytic cycle are discussed.

Ir-assisted enantioselective α-C−H functionalization of unsaturated bonds

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