The Use of pH to Influence Regio- and Chemoselectivity in the Asymmetric Aminohydroxylation of Styrenes
作者:Vitaliy Nesterenko、Joshua T. Byers、Paul J. Hergenrother
DOI:10.1021/ol027242j
日期:2003.2.1
[reaction: see text] The pH-controlled Sharplessasymmetricaminohydroxylation (AA) of styrenes provides 1-aryl-2-amino ethanols (regioisomer B) with high enantio-, chemo-, and regioselectivity. As existing AA protocols typically give regioisomer A as the major reaction product when using carbamate nitrogen sources, this method is a convenient alternative for the selective production of regioisomer
Two Syntheses of the 16- and 17-Membered DEF Ring Systems of Chloropeptin and Complestatin
作者:Amy M. Elder、Daniel H. Rich
DOI:10.1021/ol990990x
日期:1999.11.1
text] Two syntheses of a model system of the DEF ringsystem of complestatin and chloropeptin are described. The key step in both of these syntheses involves the formation of the biaryl linkage using a palladium-catalyzed Suzuki cross-coupling reaction and a catalytic enantioselective ene reaction to form the 6-bromo-D-tryptophan. Additionally, ring contraction of the 17-membered DEF ringsystem of complestatin
From Styrenes to Enantiopure α-Arylglycines in Two Steps
作者:K. Laxma Reddy、K. Barry Sharpless
DOI:10.1021/ja9728177
日期:1998.2.1
Direct enantioselective synthesis of (R)- and (S)-N-Cbz- or N-BOC-protected alpha-arylglycinols from styrenes via catalytic asymmetric aminohydroxylation, with enantioselectivities up to 99% and isolated yields up to 80%, is described. In a subsequent oxidation step, these glycinols yield the corresponding carbamate-protected alpha-arylglycines.