Ring Enlargement Reaction of C,N-Cyclic-N′-acyl Azomethine Imines with Sulfonium Ylide: An Efficient Synthesis of 3-Benzazepine Derivatives
摘要:
Highly efficient formation of 3-benzazepine derivatives has been achieved, based on the ring expansion reaction of C,N-cyclic-N'-acyl azomethine imines with sulfonium ylide generated in situ from the corresponding sulfonium salt. The reactions proceeded smoothly to afford the tricyclic 3-benzazepine derivatives in good to high yields. A wide range of C,N-cyclic N'-acyl azomethine imines were applicable to this reaction.
with azomethineimines has successfully been developed under mild reaction conditions, affording biologically interesting tetrahydropyrazoloisoquinoline derivatives in high to excellent yields and with excellent stereoselectivity. The reaction follows a tandem [3+2] cycloaddition/allylation/elimination of AcOH pathway. Allenyl carbinol acetates also reacted well with in situ generated azomethine imine
between bi‐ or mono‐N‐protected Dha and C,N‐cyclic azomethine imines, which afford various quaternary amino acids with diverse scaffolds, is disclosed. Specifically, normal‐electron‐demand 1,3‐DC reaction occurs between bi‐N‐protected Dha and C,N‐cyclic azomethine imines, while inverse‐electron‐demand 1,3‐DC reaction occurs between mono‐N‐protected Dha and C,N‐cyclic azomethine imines. Above all, the
A phosphane‐catalyzed [3+3] annulation of azomethineimines with ynones has been developed. Under mild reaction conditions, the reaction proceeds smoothly to afford tricyclic dinitrogen‐fused heterocyclic compounds in moderate to excellent yields with moderate to excellent stereoselectivies. Using a chiral phosphine as the catalyst, the reaction could work to give the cycloadduct in moderate yield
N-Heterocyclic carbene-catalyzed [2+3] cyclocondensation of α-chloroaldehydes with azomethine imines
作者:Zhong-Hua Gao、Xiang-Yu Chen、Jin-Tang Cheng、Wei-Lin Liao、Song Ye
DOI:10.1039/c5cc01238d
日期:——
The N-heterocyclic carbene-catalyzed enantioselective [2+3] cyclocondensation of α-chloroaldehydes with azomethine imines was developed to give the corresponding pyrazolidinones in good yields with excellent enantioselectivities.
Asymmetric Synthesis of Tetrahydroquinolines through a [3+2] Cycloaddition Controlled by Dienamine Catalysis
作者:Wenjun Li、Jia Wei、Qianfa Jia、Zhiyun Du、Kun Zhang、Jian Wang
DOI:10.1002/chem.201402089
日期:2014.5.26
A dienamine‐mediated enantioselective 1,3‐dipolar cycloaddition catalyzed by a chiral prolinol silyl ether catalyst has been developed. Removal of the benzamide group of the intermediates could furnish chiral C‐1 substituted tetrahydroisoquinolines (see scheme) in high yields and excellent stereoselectivities.