Stereoselective route to 15N-labeled-β-deuterated amino acids: synthesis of (2S,3R)-[3-2H,15N]-phenylalanine
作者:Derek W. Barnett、Michael J. Panigot、Robert W. Curley
DOI:10.1016/s0957-4166(02)00487-1
日期:2002.9
(2S,3R)-[3-2H,15N]-Phenylalanine hydrochloride was synthesized utilizing 15N-labeled 8-phenylmenthylhippurate as a chiral glycine equivalent. The key step in the synthesis was the alkylation of the glycine template with (S)-(+)-benzyl-α-d-mesylate. The doubly labeled alkylation product was obtained in 89% yield with 92% de at the α-carbon and 74% de at the β-carbon. The nature of the electrophile employed
Photochemical Generation of Highly Destabilized Vinyl Cations: The Effects of α- and β-Trifluoromethyl versus α- and β-Methyl Substituents
作者:Kaj van Alem、Geerte Belder、Gerrit Lodder、Han Zuilhof
DOI:10.1021/jo0487956
日期:2005.1.1
primarily generated α-CH3 and α-CF3 vinylcations, or from the α-CH3 vinylcation formed from the β-CH3 vinylcationvia a 1,2-phenyl shift. The β-CF3 vinylcation reacts with methanol yielding nucleophilic substitution products, no migration of the phenyl ring producing the α-CF3 vinylcation occurs. The α-CF3 vinylcation, which is the most destabilized vinylcation generated thus far, gives a 1,2-fluorine
Chirally deuterated benzyl chlorides from benzyl alcohols via hexachloroacetone/polymer-supported triphenylphosphine: synthesis of protected (2<i>S</i>, 3<i>S</i>)-[3-<sup>2</sup>H,<sup>15</sup>N]-tyrosine
作者:Derek W. Barnett、Maryanne S. Refaei、Robert W. Curley
DOI:10.1002/jlcr.3004
日期:2013.1
Chirally deuterated benzyl chlorides were prepared using novel, general hexachloroacetone/polymer-supported triphenylphosphine treatment of chirally deuterated benzyl alcohols. Doubly labeled protected tyrosine was obtained in 62% yield with 86% de at the α-carbon and 82% de at the β-carbon. Key in the synthesis was the alkylation of (15)N-labeled (-)-8-phenylmenthylhippurate with R-(-)-4-triisopr