Both a strong electron donor (IPr) and a strong electron acceptor (P(OPh)3) are necessary for a highly selective, nickel-catalyzed coupling reaction between alkenes, aldehydes, and silyltriflates. Without the phosphite, catalysis is not observed and several side reactions are observed. The phosphite appears to suppress the formation of these byproducts and rescue the catalytic cycle by accelerating reductive elimination from an (IPr–Ni–H)(OTf) complex.
for the regio- and stereoselective synthesis of trisubstituted allyl diarylphosphonates from the corresponding disubstituted allyl silyl ethers, circumventing the challenges related to the preparation and availability of stereodefined trisubstituted olefins. A closely related arylation reaction was also discovered during the methodology development. By simply switching the reaction medium, high phos
The PtCl2-catalyzed hydrosilylation of terminal alkynes with triethylsilane and subsequent alkenylation of aldehydes with the resultant (E)-alkenylsilanes in a one-pot manner are described. By adding p-benzoquinone and Lil, the latter alkenylation step proceeds smoothly to give allyl silyl ethers in moderate to high yields. This one-pot alkenylation is tolerant to a reasonable range of functional groups. PtCl2 plays a dual role as hydrosilylation and alkenylation catalysts.