Copper(II) mediated regioselective acetoxylation of allylic acetates and 1,4-diacetoxylation of alkenes
作者:István Macsári、Kálmán J. Szabó
DOI:10.1016/s0040-4039(98)01304-5
日期:1998.8
Copper(II) chloride in presence of lithium chloride in acetic acid oxidizes allylic acetates with high regioselectivity. Tandem allylic CH bond functionalization of unsubstituted alkenes could be accomplished by using reagent together with catalytic amounts of palladium(II) salts.
Synthesis of Vicinal Aminoalcohols by Stereoselective Aza-Wacker Cyclizations: Access to (−)-Acosamine by Redox Relay
作者:Adam B. Weinstein、David P. Schuman、Zhi Xu Tan、Shannon S. Stahl
DOI:10.1002/anie.201305926
日期:2013.11.4
Diastereoselective aza‐Wacker cyclization of O‐allyl hemiaminals under aerobic conditions enables efficient access to 1,2‐aminoalcohol derivatives from allylic alcohols. The scope of this method is presented and its utility is highlighted in a streamlined synthesis of the biologically important aminosugar (−)‐acosamine. Cbz=benzyloxycarbonyl, TBDPS=tert‐butyldiphenylsilyl, TBS=tert‐butyldimethylsilyl
Comparative studies about the hydroamination of unactivatedalkenes and dienes catalyzed by either cationic gold(I) triphenyl phosphite complexes or silver salts were performed using sulfonamides, anilines and carbamates as nucleophiles. Gold-catalyzed reactions generally, need lower loadings than those carried out with silver salts. Simple alkenes react only with sulfonamides and weak aromatic amines
Silver-Catalyzed Intermolecular Hydroamination of Alkenes and 1,3-Dienes
作者:Carmen Nájera、Xavier Giner
DOI:10.1055/s-0029-1218297
日期:2009.12
Silver triflate is used as efficient catalyst for the intermolecular addition of 4-toluenesulfonamide to alkenes under thermal or microwave heating. The hydroamination of 1,3-dienes can be performed at 85 °C with low catalyst loading (0.1-5 mol%) or at room temperature using 1 mol% of AgOTf, the use of HOTf affording similar results.
Herein, we describe the intermolecular amination of allyl alcohols with sulfamates, which have been underutilized as nitrogen nucleophiles for allylic amination. Methyl sulfamate is a good nucleophile in the presence of mercuric triflate and efficiently generates monoallylation products in excellent yield at room temperature. Furthermore, the solid-supported mercuric catalyst silaphenyl mercuric triflate