Pd(II)-catalyzed oxidative cyclization reaction for the preparation of 2-substituted 1,2,3,4-tetrahydroquinolines with halide functionality
摘要:
The first Pd(II)-catalyzed oxidative cyclization reaction was developed for preparation of 2-substituted 1,2,3,4-tetrahydroquinolines from olefinic tosylamides. Under the optimized conditions, up to 86% yield was obtained. This reaction provides direct and easy access to 2-substituted 1,2,3,4-tetrahydroquinolines with halide functionality. (C) 2010 Elsevier Ltd. All rights reserved.
The [4+1] cycloaddition reaction of bifunctional amino reagents has been achieved with in situ formed aza‐ortho‐quinonemethides. Specifically, N‐(tosyloxy)carbamates were used as an N1 synthon and bifunctional amino reagents for this transformation, which provides a metal‐free, catalyst‐free, and oxidant‐free strategy to form nitrogen‐nitrogen bonds.
Synthesis of Furo[3,2-<i>b</i>]quinolines and Furo[2,3-<i>b</i>:4,5-<i>b′</i>]diquinolines through [4 + 2] Cycloaddition of Aza-<i>o</i>-Quinone Methides and Furans
作者:Lu Lei、Yi-Yun Yao、Li-Juan Jiang、Xiuqiang Lu、Cui Liang、Dong-Liang Mo
DOI:10.1021/acs.joc.9b02953
日期:2020.3.6
An approach for the construction of furo[3,2-b]quinolines and furo[2,3-b:4,5-b']diquinolines is developed through a metal-free [4 + 2] cycloaddition of easily available in situ generated aza-o-quinone methides and furans. The reaction tolerates a wide range of aza-o-quinone methides and substituted furans to afford the corresponding dihydro- or tetrahydrofuroquinolines in good to excellent yields.
The base-induced formal [4+3] cycloaddition reaction of C,N-cyclic azomethine imines with aza-ortho-quinone methides, generated in situ, is reported. This protocol provided an efficient method for the synthesis of biologically important 1,2,4-triazepine derivatives, with a wide substrate scope and excellent functional-group tolerance, and it gives moderate to excellent yields under mild conditions
A Pd(II)‐catalyzed oxidative cyclization of olefinic tosylamides was developed for the preparation of aryl‐fused and N‐containing six‐membered heterocycles. Under optimized conditions the reaction proceeded with high activity and selectivity, with yields of up to 83% being obtained. This procedure provides a facile and efficient route to the aforementioned heterocycles with 2‐acetoxy functionality
Batting the ylides: A simple procedure carried out under mild conditions allows the direct and efficientsynthesis of structurally diverse indoles. This approach involves a cascadereaction of sulfurylides and N‐(ortho‐chloromethyl)arylamides (see scheme).