A Highly Diastereo- and Enantioselective Hg(II)-Catalyzed Cyclopropanation of Diazooxindoles and Alkenes
作者:Zhong-Yan Cao、Feng Zhou、Yi-Hua Yu、Jian Zhou
DOI:10.1021/ol302998m
日期:2013.1.4
It is reported for the first time that Hg(II) can catalyze the cyclopropanation of diazo reagents and alkenes, which contributes to the unprecedented highlydiastereo- and enantioselective synthesis of spirocyclopropyloxindoles.
11–21-membered intramolecular macrocyclic sulfonium ylides using catalytic Rh2(OAc)4 is presented. Using this approach, a wide variety of sulfur-macrocycles incorporating the oxindole unit were produced in good yields and with high diastereoselectivity. Interestingly, tetracyclic macrocycles were also attained in good yields and with good regioselectivity using the disclosed sulfonium ylides. Ring-opening
In the presence of DIPEA (diisopropylethylamine), a formal [3+2] cycloaddition reaction between diazooxindoles and oxazol‐5‐(4H)‐ones takes place easily to give new 3‐(1H‐1,2,4‐triazol‐1‐yl)indolin‐2‐ones in 61–98 % yield. The structure of the target molecules was confirmed by single‐crystal X‐ray structure analysis.
在存在DIPEA(二异丙基乙胺)的情况下,重氮恶唑与恶唑-5-(4 H)-酮之间的[3 + 2]环加成反应很容易发生,从而生成新的3-(1 H -1、1,2,4-三唑‐1-yl)indolin-2-ones的产率为61–98%。通过单晶X射线结构分析确认了目标分子的结构。
Asymmetric sequential Au(<scp>i</scp>)/chiral tertiary amine catalysis: an enone-formation/cyanosilylation sequence to synthesize optically active 3-alkenyloxindoles from diazooxindoles
An unprecedented sequential gold-catalyzed enone-formation and bifunctional tertiary amine mediated asymmetric cyanosilylation reaction is developed, allowing highly enantioselective synthesis of 3-alkenyloxindoles from diazooxindole, furan and trimethylsilyl cyanide (TMSCN).
Sequential Au(<scp>i</scp>)/chiral tertiary amine catalysis: a tandem C–H functionalization of anisoles or a thiophene/asymmetric Michael addition sequence to quaternary oxindoles
作者:Zhong-Yan Cao、Yu-Lei Zhao、Jian Zhou
DOI:10.1039/c5cc10096h
日期:——
We report an unprecedented sequential Au(I)/bifunctional tertiary amine catalysis, which enables a tandem C-H functionalization of weak nucleophiles (anisole or thiophene) and asymmetric Michael addition for the highly enantioselective synthesis...