Exo/endo selectivity-control in Lewis-acid catalyzed tandem heterocyclization/formal [4+3] cycloaddition: synthesis of polyheterocycles from 2-(1-alkynyl)-2-alken-1-ones and 1,3-diphenylisobenzofuran
作者:Hongyin Gao、Xingxing Wu、Junliang Zhang
DOI:10.1039/c0cc02778b
日期:——
tandem heterocyclization/formal [4+3] cycloaddition was developed, which provides rapid, efficient and stereoselective access to highly fused polyheterocycles from readily available 2-(1-alkynyl)-2-alken-1-ones and 1,3-diphenylisobenzofuran under mild conditions.
The mysterious cyclizations of gold: An asymmetric gold(I)‐catalyzed formal [3+3] cycloaddition of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with nitrones has been developed. Compound 1 was found to be an effective and reliable chiral catalyst, as well as the commonly used 2, for this gold‐catalyzed reaction. Tf=trifluoromethanesulfonyl.
Highly Substituted Furo[3,4-<i>d</i>][1,2]oxazines: Gold-Catalyzed Regiospecific and Diastereoselective 1,3-Dipolar Cycloaddition of 2-(1-Alkynyl)-2-alken-1-ones with Nitrones
作者:Feng Liu、Yihua Yu、Junliang Zhang
DOI:10.1002/anie.200901299
日期:2009.7.13
Rapid access: A gold(I)‐catalyzed1,3‐dipolarcycloaddition of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with nitrones provides a practical, regiospecific, and stereoselective access to highlysubstituted fused bicyclic furo[3,4‐d][1,2]oxazines under mild conditions (see scheme). These fused heterobicyclic compounds can be readily converted into furans or 3,6‐dihydro‐2H‐1,2‐oxazines in a chemoselective fashion
快速获得:金(I)催化的2-(1-炔基)-2-烯丙基-1-酮与1,3-偶极环的加成反应,提供对高取代的稠合双环呋喃的实用,区域特异性和立体选择性的访问[ 3,4- [ d ] [1,2]恶嗪在温和的条件下(请参阅方案)。这些稠合的杂环双环化合物可以以化学选择性方式轻易地转化为呋喃或3,6-二氢-2 H -1,2-恶嗪。
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.
Dinucleophilic Reactivity of Isocyanoacetate: Base-Catalyzed One-Pot Access to 4-Azafluorenes and 4-Azafluorenones
作者:Xin Wang、Jinhuan Dong、Xianxiu Xu、Bo Tang
DOI:10.1021/acs.orglett.1c03314
日期:2021.12.3
A base-catalyzed doubleannulation of isocyanoacetates with various enynones has been developed for the expeditious synthesis of 4-azafluorene and 4-azafluorenone derivatives. Against the well-known 1,3-dipolar reactivities, the active methylene and isocyano groups of isocyanoacetate serve as nucleophiles in this domino transformation.