Regioselective N-Addition/Substitution Reaction of α-Alkylidene Pyrazolinones with Propargyl Sulfonium Salts to Construct Allylthio-Containing Pyrazolones
The regioselective N-addition/substitutionreaction between α-alkylidene pyrazolinones and propargyl sulfonium salts has been developed to construct functionalized allylthio-containing pyrazolones with moderate to excellent yields. α-Alkylidene pyrazolinones act as N-nucleophilic agents which are distinguished from reported C-nucleophilic reactions. Excellent regioselectivity, readily available starting
A novel divergent domino annulation reaction of prop-2-ynylsulfonium salts with sulfonyl-protected β-amino ketones has been developed, affording various epoxide-fused 2-methylenepyrrolidines and S-containing pyrroles in moderate to excellent yields. Prop-2-ynylsulfonium salts act as C2 synthons in the reactions providing a promising epoxide-fused skeleton in a single operation with readily accessible
Isotopic labelling studies for a gold-catalysed skeletal rearrangement of alkynyl aziridines
作者:Paul W Davies、Nicolas Martin、Neil Spencer
DOI:10.3762/bjoc.7.96
日期:——
Isotopic labelling studies were performed to probe a proposed 1,2-aryl shift in the gold-catalysed cycloisomerisation of alkynyl aziridines into 2,4-disubstituted pyrroles. Two isotopomers of the expected skeletalrearrangement product were identified using (13)C-labelling and led to a revised mechanism featuring two distinct skeletalrearrangements. The mechanistic proposal has been rationalised against
进行同位素标记研究以探测在金催化的炔基氮丙啶环异构化成 2,4-二取代吡咯中所提出的 1,2-芳基位移。使用 (13) C 标记确定了预期骨骼重排产物的两种同位素,并导致了具有两种不同骨骼重排的修订机制。针对一系列 (13) C 和氘标记底物的反应,该机制建议已被合理化。
Divergent Domino Reactions of Prop-2-ynylsulfonium Salts: Access to Sulfur-Containing Benzo-Fused Dioxabicyclo[3.3.1]nonanes and Dihydrofuro[2,3-<i>c</i>]chromenes
作者:Yiming Zhou、Yu Chen、You Huang
DOI:10.1021/acs.orglett.0c02025
日期:2020.8.7
domino annulation reactions between 2-hydroxy-2-methylchromene derivatives and prop-2-ynylsulfonium salts have been developed. Specifically, a sequential [4 + 2] and [4 + 2] annulation reaction occurred in 1,2-dichloroethane affording sulfur-containing benzo-fused dioxabicyclo[3.3.1]nonanes. In contrast, by changing the solvent to toluene, the reaction course switched to a [4 + 2] and [4 + 1] annulation
已经开发了2-羟基-2-甲基苯甲基衍生物和丙-2-炔基ulf盐之间的溶剂控制的发散性多米诺环化反应。具体地,在[1,2-二氯乙烷]中发生顺序的[4 + 2]和[4 + 2]环化反应,得到含硫的苯并稠合的二氧杂双环[3.3.1]壬烷。相反,通过将溶剂改变为甲苯,反应过程切换为[4 + 2]和[4 +1]环化反应,得到二氢呋喃[2,3- c ]二甲基苯。值得注意的是,丙-2-炔基salt盐首次以其γ-碳原子参与转化。
A Formal [3+2] Annulation of
<i>β</i>
‐Oxoamides and 3‐Alkyl‐ or 3‐Aryl‐Substituted Prop‐2‐Ynyl Sulfonium Salts: Substrate‐Controlled Chemoselective Synthesis of Substituted
<i>γ</i>
‐Lactams and Furans
A substrate‐controlled synthesis of substituted γ‐lactams and furans has been developed via a formal [3+2] annulation of β‐oxoamides and 3‐alkyl/arylprop‐2‐ynyl sulfonium salts in the presence of cesium carbonate in a chemoselective manner. This novel protocol features easily available starting materials, mild reaction conditions, simple execution, and good to excellent yields of products.