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.
New Uses for the Burgess Reagent in Chemical Synthesis: Methods for the Facile and Stereoselective Formation of Sulfamidates, Glycosylamines, and Sulfamides
作者:K. C. Nicolaou、Scott A. Snyder、Deborah A. Longbottom、Annie Z. Nalbandian、Xianhai Huang
DOI:10.1002/chem.200400503
日期:2004.11.19
Although the Burgess reagent (methoxycarbonylsulfamoyltriethylammonium hydroxide, inner salt) has found significant use in chemical synthesis as a dehydrating agent, almost no work has been directed towards its potential in other synthetic applications. As this article will detail, we have found that the Burgess reagent is remarkably effective at accomplishing a number of non-dehydrative synthetic
Total Synthesis of (−)-Rhazinilam and Formal Synthesis of (+)-Eburenine and (+)-Aspidospermidine: Asymmetric Cu-Catalyzed Propargylic Substitution
作者:Andrej Shemet、Erick M. Carreira
DOI:10.1021/acs.orglett.7b02619
日期:2017.10.20
A total synthesis of (−)-rhazinilam and formal syntheses of (+)-eburenine and (+)-aspidospermidine that rely on a copper(I)-catalyzed asymmetric propargylic substitution as the key step are reported. A salient feature of the reaction is the asymmetric construction of a quaternary stereocenter in high yield and enantiomeric excess.