烯酰胺中β-C(sp 2 )-H键的直接官能化在有机合成领域引起了越来越多的关注。然而,这些显着的进步主要依赖于过渡金属。通过有机催化取得的成功有限。在此,我们报道了CPA催化的烯酰胺级联分子内环化的β-C(sp 2 )-H功能化,合成了带有偕二氟亚甲基的手性二氢嘧啶并[1,6- a ]吲哚。此外,该方法能够以中等到高产率合成具有出色对映选择性的多种手性二氢嘧啶并[1,6- a ]吲哚。
Silver-catalyzed one-pot cyclization/fluorination of 2-alkynylanilines: highly efficient synthesis of structurally diverse fluorinated indole derivatives
作者:Lei Yang、Yuanhong Ma、Feijie Song、Jingsong You
DOI:10.1039/c3cc49851d
日期:——
Highly efficient approaches to obtain structurally diverse fluorinated indolederivatives have been realized through the Ag-catalyzed one-pot cyclization/fluorination of 2-alkynylanilines in the presence of NFSI or Selectfluor.
The scope and limitations of gold-catalyzed tandem cycloisomerization/fluorination reactions of unprotected 2-alkynylanilines to have access to 3,3-difluoro-2-aryl-3H-indoles and 3-fluoro-2-arylindoles are described. An unprecedented aminoauration/oxidation/fluorination cascade reaction of 2-alkynylanilines bearing a linear alkyl group on the terminal triple bond is reported.
Exploration of Forbidden Povarov Processes as a Source of Unexpected Reactivity: A Multicomponent Mannich-Ritter Transformation
作者:Sara Preciado、Esther Vicente-García、Salomé Llabrés、F. Javier Luque、Rodolfo Lavilla
DOI:10.1002/anie.201202927
日期:2012.7.9
geometrically or electronically restricted imines for Povarov‐type processes does not afford the anti‐Bredt tetrahydroquinolines, but leads instead to highly functionalized structures through novel reaction pathways (see picture; LA=Lewis acid). The exploration of “forbidden” routes constitutes a valuable approach in the search for new multicomponent reactions.
当一扇门关闭时,一个窗户就会打开!在Povarov型工艺中使用受几何或电子限制的亚胺并不能提供抗Bredt四氢喹啉,而是通过新颖的反应途径获得高度官能化的结构(参见图片; LA =路易斯酸)。探索“禁止”路线是寻找新的多组分反应的一种有价值的方法。
B(C6F5)3/CPA‐Catalyzed Aza‐Diels‐Alder Reaction of 3,3‐Difluoro‐2‐Aryl‐3H‐indoles and Unactivated Dienes
Herein, we describe B(C6F5)3/CPA-catalyzed enantioselective aza-Diels–Alder reaction of 3,3-difluoro-2-Aryl-3H-indoles with unactivated dienes to access chiral 10,10-difluoro-tetrahydropyrido[1,2-a]indoles in good yields with good to excellent ee. The resulting cycloadducts containing an CF2 unit could be further transformed into other important building blocks.
在此,我们描述了 B(C 6 F 5 ) 3/ CPA 催化的 3,3-二氟-2-芳基-3 H-吲哚与未活化的二烯的对映选择性氮杂-狄尔斯-阿尔德反应,得到手性 10,10-二氟-四氢吡啶并[1,2- a ]吲哚的产率良好,ee 良好至优异。所得的含有CF 2单元的环加合物可以进一步转化为其他重要的结构单元。
One-Pot Gold-Catalyzed Aminofluorination of Unprotected 2-Alkynylanilines
A tandem gold(I)-catalyzed aminocylization/fluorination and a two-step, one-pot gold(III)-catalyzed cyclization/electrophilic fluorination provide a convenient and general method for the synthesis of 3,3-difluoro-2-substituted-3H-indoles in good yield under mild conditions. Extension of the procedure to the synthesis of 2-aryl-3-fluoro-1H-indoles is described. The reaction proceeds smoothly in green ethanol and does not require any base, acid, or N-protective group.