Development of regioselective [2 + 3] cycloaddition reactions of nitrile oxides with alkenes using intramolecular reactions through oxime groups [1]
作者:Nao Umemoto、Ayumi Imayoshi、Kazunori Tsubaki
DOI:10.1016/j.tet.2022.132833
日期:2022.8
oxime group and demonstrated their intramolecular [2 + 3] cycloaddition reactions. The desired cycloadducts were obtained in high yields and as single regioisomers. Furthermore, face-selective cycloaddition reactions were achieved by introducing a stereocenter into the linker moiety, affording the desired cycloadducts with good diastereoselectivity.
A one-pot synthesis of trifluoromethylated α,β-unsaturated esters
作者:Yanchang Shen、Yuejun Xiang
DOI:10.1016/s0022-1139(00)80137-2
日期:1991.4
Trifluoromethylated alpha,beta-unsaturated esters were conveniently synthesized by reaction of organolithium compounds with a fluorinated biscarbonylphosphonium salt which was prepared in situ by acylation of the corresponding phosphorane with trifluoroacetic anhydride.
A newly-designed PE-supported arsine for efficient and practical catalytic Wittig olefination
A newly designed PE-supported arsine has been developed as an excellent catalyst for catalytic Wittig-type olefination. Simple ketones, in particular inactive ketones prove to be suitable substrates for the first time. This reaction provides an easy access to di-, tri-, and tetra-substituted olefins in high yield.
Diastereo- and Enantioselective Synthesis of Structurally Diverse Succinate, Butyrolactone, and Trifluoromethyl Derivatives by Iridium-Catalyzed Hydrogenation of Tetrasubstituted Olefins
作者:Sutthichat Kerdphon、Sudipta Ponra、Jianping Yang、Haibo Wu、Lars Eriksson、Pher G. Andersson
DOI:10.1021/acscatal.9b01508
日期:2019.7.5
A highly efficient iridium N,P-ligand-catalyzed asymmetric hydrogenation of functionalized tetrasubstituted olefins lacking a directing group has been developed. Various structural diverse chiral succinate derivatives were obtained in high yields and excellent enantio- and diastereoselectivities (up to 99% ee) using 0.5–1.0 mol % catalyst loadings. This stereoselective reaction is applicable for the