Fang, Yuan-QingTadross, Pamela M.Jacobsen, Eric2016-01-042014Fang, Yuan-Qing, Pamela M. Tadross, and Eric N. Jacobsen. 2014. “Highly Enantioselective, Intermolecular Hydroamination of Allenyl Esters Catalyzed by Bifunctional Phosphinothioureas.” Journal of the American Chemical Society 136 (52): 17966-17968. doi:10.1021/ja5117638. http://dx.doi.org/10.1021/ja5117638.0002-7863http://nrs.harvard.edu/urn-3:HUL.InstRepos:23993659Bifunctional phosphinothiourea catalysts have been developed successfully for the highly regio- and enantioselective γ-hydroamination of allenyl and propargyl esters with N-methoxy carbamate nucleophiles to yield α,β-unsaturated γ-amino acid ester products. In the case of propargyl ester substrates, the reaction proceeds through reversible phosphinothiourea-catalyzed isomerization to the corresponding allenyl ester. The high enantioselectivity of the process is attributed to a cooperative conjugate addition of a thiourea-bound carbamate anion to a vinyl phosphonium ion resulting from covalent activation of the allenyl ester substrate.en-USJournal Article2016-01-0410.1021/ja5117638