title: Double-asymmetric hydrogenation strategy for the reduction of 1,1-diaryl olefins applied to an improved synthesis of CuIPhEt, a C2-symmetric N-heterocyclic carbenoid.
abstract: A library of iridium and rhodium phosphine catalysts have been screened for the double-asymmetric hydrogenation of 2,6-di-(1-phenylethenyl)-4-methylaniline to produce the C2-symmetric aniline precursor of the N-heterocyclic carbenoid CuIPhEt. The best catalyst produced the desired enantiomer in 98.6% selectivity. This rare example of a highly selective hydrogenation of a 1,1-diaryl olefin enables a four-step asymmetric synthesis of the C2-symmetric phenylethyl imidazolium ion (IPhEt) from p-toluidine and phenylacetylene and its conversion to the hydrosilylation catalyst CuIPhEt.
authors: Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, United States.
authors: Elizabeth
authors: E
authors: Spahn
authors: Abigail
authors: A
authors: Albright
authors: Michael
authors: M
authors: Shevlin
authors: Larissa
authors: L
authors: Pauli
authors: Andreas
authors: A
authors: Pfaltz
authors: Robert E
authors: RE
authors: Gawley
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D000814:Aniline Compounds / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D006865:Hydrogenation; D015394:Molecular Structure; D013237:Stereoisomerism; D014052:Toluidines / Q000737:chemistry*
chemical_list: D000475:Alkenes; D000480:Alkynes; D000814:Aniline Compounds; D056831:Coordination Complexes; D006571:Heterocyclic Compounds; D014052:Toluidines; D003300:Copper
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