一系列含有环戊烯环或杂环的2-炔基羰基化合物可通过1,2-烷基迁移过程转化为各种稠合的二氢苯并呋喃和四氢呋喃[2,3- c ]吡啶。当使用阳离子金(I)催化剂时,这两个反应都具有出色的区域选择性和立体选择性。在不同条件下处理4-苯乙烯基环戊-1-烯羧酸酯可提供一系列高度官能化的二氢苯并呋喃和二氢异苯并呋喃。观察到产物选择性的差异,这取决于所用银盐的阴离子。有趣的是,环-稠合四氢喹啉通过C的手段仅经历-1,2'-烷基迁移反应C裂解/环化序列以提供四氢a庚因衍生物。机理研究表明,金络合物通过协同反应途径催化1,2-烷基迁移反应,并通过逐步反应途径催化1,2'-烷基迁移反应。
Highly Substituted 2,3-Dihydroisoxazoles by Et<sub>3</sub>N-Catalyzed Tandem Reaction of Electron-Deficient 1,3-Conjugated Enynes with Hydroxylamines
作者:Xiuzhao Yu、Bo Du、Kai Wang、Junliang Zhang
DOI:10.1021/ol100490y
日期:2010.4.16
reaction of electron-deficient 1,3-conjugated enynes with hydroxylamines was developed which provided rapid, metal-free, and regioselective access to highly substituted multifunctionalized 2,3-dihydroisoxazoles under mild conditions. The reactions of 3-(2-arylethynyl)-4H-chromen-4-ones with hydroxylamines afford β-amino enones under the same reaction conditions.
Cationic Rhodium(I)-Catalyzed Regioselective Tandem Heterocyclization/[3+2] Cycloaddition of 2-(1-Alkynyl)-2-alken-1-ones with Alkynes
作者:Hongyin Gao、Junliang Zhang
DOI:10.1002/chem.201103924
日期:2012.3.5
RhI in two minds: A RhI‐catalyzed tandem heterocyclization/[3+2] cycloaddition reaction was developed that provides rapid, efficient, and stereoselective access to highly substituted cyclopenta[c]furans from readily available 2‐(1‐alkynyl)‐2‐alken‐1‐ones and alkynes (see scheme). The cationic RhI acts as both a Lewis acid and a conventional transition‐metal catalyst, providing the first example of
Tetrasubstituted allenes by Pd0-catalyzed three-component tandem Michael addition/cross-coupling reaction
作者:Yuanjing Xiao、Junliang Zhang
DOI:10.1039/b919060k
日期:——
A Pd(0)-catalyzed three-component tandem Michaeladdition/cross-couplingreaction of electron-deficient enynes with nucleophiles and aryl halides was developed, which provides general, efficient, and regioselective access to multi-functionalized tetra-substituted allenes.
Tetrasubstituted furans by PdII/CuI-cocatalyzed three-component domino reactions of 2-(1-alkynyl)-2-alken-1-ones, nucleophiles and diaryliodonium salts
作者:Wenbo Li、Junliang Zhang
DOI:10.1039/c0cc03450a
日期:——
A novel Pd(OAc)(2)/CuI-cocatalyzed three-componentreaction of 2-(1-alkynyl)-2-alken-1-ones, nucleophiles and diaryliodonium salts has been developed. The procedure allows the synthesis of tetrasubstitutedfurans in good to high yields under mild conditions.
Tetrasubstituted Furans by Pd<sup>II</sup>-Catalyzed Three-Component Domino Reactions of 2-(1-Alkynyl)-2-alken-1-ones with Nucleophiles and Vinyl Ketones or Acrolein
作者:Renrong Liu、Junliang Zhang
DOI:10.1002/chem.200901386
日期:2009.9.21
Multicomponent reaction: A novel PdII‐catalyzed three‐component cascade reaction of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with nucleophiles and vinylketones has been developed (see scheme), which provides efficient, general, and atom‐economic access to tetrasubstituted, multifunctionalized furans.