Silver-catalyzed carbon–phosphorus functionalization of N-(p-methoxyaryl)propiolamides coupled with dearomatization: access to phosphorylated aza-decenones
A highly diastereoselective dearomatization of indolesviapalladium-catalyzed decarboxylative alkynyl termination was developed. This protocol provides dissimilar tetracyclic and tetrasubstituted indoline scaffolds bearing congested stereocenters, which led to operationally simple conditions, short time, and broad substrate scope. Additionally, this reaction system could be scaled to gram quantities
PROCESS FOR PREPARING A PROPIOLIC ACID OR A DERIVATIVE THEREOF
申请人:Goossen Lukas J
公开号:US20140012000A1
公开(公告)日:2014-01-09
The invention relates to a process for preparing a propiolic acid or a derivative thereof by reacting a terminal alkyne with carbon dioxide, which comprises performing the reaction in the presence of a base and a copper complex, especially a copper (I) complex having at least one ligand, at least one of the ligands of the copper complex being selected from monodentate ligands which have an aminic or iminic nitrogen atom capable of coordination with copper, and polydentate ligands having at least two atoms or atom groups which are capable of simultaneous coordination with copper and are selected from nitrogen, oxygen, sulfur, phosphorus and carbene carbon.
TsNBr2 promoted decarboxylative bromination of α,β-unsaturated carboxylic acids
作者:Debojit Hazarika、Prodeep Phukan
DOI:10.1016/j.tetlet.2018.11.041
日期:2018.12
A rapid process for decarboxylative bromination of α,β-unsaturatedcarboxylicacids have been developed using N,N-dibromo-p-toluenesulfonamide (TsNBr2). Treatment of cinnamic acids with TsNBr2 in presence of potassium carbonate in acetonitrile produces corresponding β-bromostyrenes at room temperature. Exclusive formation of (E)-β-bromostyrenes was observed in a stereoselective manner within a very
Substrate‐Assisted, Transition‐Metal‐Free Diboration of Alkynamides with Mixed Diboron: Regio‐ and Stereoselective Access to
<i>trans</i>
‐1,2‐Vinyldiboronates
作者:Astha Verma、Russell F. Snead、Yumin Dai、Carla Slebodnick、Yinuo Yang、Haizhu Yu、Fu Yao、Webster L. Santos
DOI:10.1002/anie.201700946
日期:2017.4.24
A substrate‐assisteddiboration of alkynamides using the unsymmetrical pinacolato‐1,8‐diaminonaphthalenato diboron (pinBBdan) is described. The transition‐metal‐free reaction proceeds in a regio‐ and stereoselective fashion to exclusively afford trans‐vinyldiboronates in good to excellent yields. Notably, Bdan and Bpin are installed on the α‐ and β‐carbon atoms, respectively.
Rhodium(III)-Catalyzed Regioselective Decarboxylative Cyclization for the Synthesis of 4<i>H</i>-Furo[3,2-<i>c</i>]chromen-4-one Derivatives
作者:Dandan Zha、Hongji Li、Shiqing Li、Lei Wang
DOI:10.1002/adsc.201600974
日期:2017.2.2
This contribution describes a regioselective cyclization of hypervalent iodine reagents (HIR) with propiolic acids in the presence of a rhodium catalyst. The mild decarboxylation can tolerate a wide range of groups and generates 4H‐furo[3,2‐c]chromen‐4‐one derivatives in good isolated yields.
该贡献描述了在铑催化剂存在下用丙酸对高价碘试剂(HIR)的区域选择性环化。轻度的脱羧可以耐受广泛的基团,并以良好的分离产率生成4 H-呋喃[3,2 - c ] chromen-4-one衍生物。