1-Alkylstyrenes undergo efficient hydrovinylation (addition of ethylene) in the presence of a Ni-catalyst prepared from [(allyl)NiBr](2), Na(+) [BAr(4)](-) (Ar = 3,5-bis-trifluromethylphenyl), and a phosphoramidite ligand giving products in excellent yields and enantioselectivities. In many cases phosphoramidites derived from achiral 2,2'-biphenol are almost as good as ligands derived from the more expensive enantiopure 2,2'-binaphthols. The hydrovinylation products, which carry two versatile latent functionalities, an aryl and a vinyl group, are potentially useful for the synthesis of several important natural products containing benzylic all-carbon quaternary centers.
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| http://dx.doi.org/10.1055/s-0029-1216826 | DOI Listing |
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