An Unprecedented Organocascade Synthesis of Functionalized Bicyclic Nitrones from 2‐Aminomalonate Derived Nucleophiles and 1‐Nitro‐1,3‐Enynes via Allenes Formation and Subsequent Rearrangement
作者:Wan‐Yun Huang、Ramani Gurubrahamam、Kwunmin Chen
DOI:10.1002/adsc.201801161
日期:2019.1.11
An efficient organocatalytic cascade reaction for synthesising functionalized bicyclic nitrones is reported. The reaction of dielectrophilic ethyl 2‐(nitromethylene)‐4‐arylbut‐3‐ynoate and (E)‐diethyl 2‐((2‐hydroxybenzylidene)‐amino)malonates to give a unique nitrone scaffold in the presence of a catalytic amount of DABCO is described. The working mechanism was proposed to proceed with allene formation
afforded a number of fluorine containing α aminoacids such as β-fluorinated-alanines, 2-amino-n,n,n-trifluoroalkanoic acids, and fluorinated glutamic acids as well as other γ-heteroatom substituted glutamic acids. Here, an efficient enzymatic optical resolution using hog kidney acylase was conducted to obtain both optical isomers of 2-amino-n,n,n-trifluoroalkanoic acids. In addition, a novel sulfoxide
In this paper, an asymmetricallylicalkylation of easily available azomethine ylides with Morita–Baylis–Hillman (MBH) carbonates through a copper (I)/Lewisbase cooperative catalysis strategy has been realized. The co-catalyzed asymmetricallylicalkylation provided the corresponding amino acid derivatives in up to 90% yields with up to 99% ee as well as good to excellent regioselectivity.
在本文中,通过铜(I)/刘易斯碱协同催化策略实现了易于获得的偶氮甲碱叶立德与 Morita-Baylis-Hillman(MBH)碳酸酯的不对称烯丙基烷基化。共催化的不对称烯丙基烷基化以高达 90% 的产率和高达 99% 的 ee 以及良好至极好的区域选择性提供了相应的氨基酸衍生物。
Fluorine-containing amino acids and their derivatives. 6. An efficient synthesis of β-fluorinated alanines via fluorohalomethylation of aminomalonates
作者:Tadahiko Tsushima、Kenji Kawada
DOI:10.1016/s0040-4039(00)94849-4
日期:1985.1
in good yields. These products were successfully converted to various versatile β-fluorinated alanine derivatives, i.e., β,β-difluoroalanine (), N-acyl-β-fluorodehydroalaninate (), and fluoropyruvic acid ().