Copper(I)-Catalyzed Addition of Grignard Reagents to in Situ-Derived <i>N</i>-Sulfonyl Azoalkenes: An Umpolung Alkylation Procedure Applicable to the Formation of Up to Three Contiguous Quaternary Centers
作者:John M. Hatcher、Don M. Coltart
DOI:10.1021/ja100932q
日期:2010.4.7
that has considerable potential with regard to catalysis and the direct incorporation of functionality not amenable to the use of enolate chemistry. Herein, we describe the first Cu(I)-catalyzed addition of Grignardreagents to in situ-derived N-sulfonyl azoalkenes. This method is remarkable in its ability to deliver highly sterically hindered compounds that would be difficult or impossible to synthesize
Enantioselective Addition of Alkynes to α,α-Dichlorinated Aldehydes
作者:Yeshua Sempere Molina、Jonathan Ruchti、Erick M. Carreira
DOI:10.1021/acs.orglett.6b03692
日期:2017.2.17
Enantioselective addition of terminal alkynes to α,α-dichlorinated aldehydes employing Zn(OTf)2/NME is disclosed. The propargylic alcohols obtained are accessed in good yields and high enantioselectivity from easily accessible α,α-dichloroaldehydes. The method opens new strategic opportunities for the synthesis of chlorinated natural products, such as the chlorosulfolipids.
Catalytic Asymmetric Formation of δ-Lactones from Unsaturated Acyl Halides
作者:Paolo S. Tiseni、René Peters
DOI:10.1002/chem.200902896
日期:2010.2.22
Previously unexplored enantiopure zwitterionic ammonium dienolates have been utilized in this work as reactive intermediates that act as diene components in hetero‐Diels–Alderreactions (HDAs) with aldehydes to produce optically active δ‐lactones, subunits of numerous bioactive products. The dienolates were generated in situ from E/Z mixtures of α,β‐unsaturated acid chlorides by use of a nucleophilic
Allylation with substituted vinylthionium ions from SnCl4 ionisation of 1,3- and 3,3-bis(alkyl/phenylthio) propenes
作者:Roger Hunter、Joseph P. Michael、Daryl S. Walter
DOI:10.1016/s0040-4020(01)85514-9
日期:——
α- and γ-substituted vinylthionium ions from SnCl4 ionisation of a range of substituted 1,3- and 3,3-bis (alkyl/phenylthio) propenes allylate enol allyl ethers in good yield. Levels of regioselectivity are sterically dependent and in the case of methyl as γ-substituent may be controlled by the steric bulk of the sulfur substituent. As with the Pummerer methodology, γ-addition generally gave (E)-vinyl
[EN] SELECTIVE SPHINGOSINE-1-PHOSPHATE RECEPTOR ANTAGONISTS<br/>[FR] ANTAGONISTES SÉLECTIFS DES RÉCEPTEURS DE SPHINGOSINE-1-PHOSPHATE
申请人:ALLERGAN INC
公开号:WO2011028927A1
公开(公告)日:2011-03-10
Described herein are compounds of the formula useful as antagonists of sphingosine-1- phosphate receptors. Further described herein is the use of these compounds and related pharmaceutical compositions to treat disorders associated with sphingosine-1 -phosphate -3 (S1P3) receptor modulation.