An evidence of contact ion pair in β-(acyloxy)alkyl radical heterolysis during copper(I)-mediated synthesis of trisubstituted alkenes
作者:Ram N. Ram、Ram K. Tittal
DOI:10.1016/j.tetlet.2014.06.008
日期:2014.8
The first evidence for a unified mechanism of heterolysis in β-(acyloxy)alkylradical involving contact ion pair (CIP) is presented for both fragmentation and rearrangement of the acyloxy group in the reaction of 1-alkoxy-2,2,2-trichloroethyl acetate with 2 mol equiv each of CuCl and bpy in refluxing DCE under a N2 atmosphere and availed this reaction for the synthesis of Z-stereoselective trisubstituted
提出了涉及接触离子对(CIP)的β-(酰氧基)烷基自由基杂合的统一机理的第一个证据,用于1-烷氧基-2,2,2-三氯乙基的反应中酰氧基的断裂和重排。在N 2气氛下,在回流的DCE中,分别用2摩尔当量的CuCl和bpy制成乙酸酯,并将该反应用于合成Z-立体选择性三取代烯烃。通过在1 H和13 C NMR光谱中某些相关信号的化学位移值的均匀模式来指定三取代烯烃的立体化学。Z -1-氯-2-(4-硝基苄氧基)乙酸乙烯酯的X射线衍射光谱进一步证实了这种归属。
1,2-H Shift in Copper−Chlorocarbenoid Intermediate during CuCl/bpy-Promoted Stereoselective Dechlorination of 2,2,2-Trichloroethyl Alkyl Ethers to (<i>Z</i>)-1-Alkoxy-2-chloroethenes
作者:Ram N. Ram、T. P. Manoj
DOI:10.1021/ol8006524
日期:2008.6.5
Reaction of 2,2,2-trichloroethyl alkyl ethers with 2 molar equiv of CuCl/bpy in refluxing DCE yielded (2)-1-alkoxy-2-chloroethenes stereoselectively as the major product via 1,2-H shift in copper-chlorocarbenoid intermediate. 2,2,2-Trichloroethyl carboxylates undergo a radical 1,2-acyloxy shift under similar conditions.
SUDA MINORU; FUKUSHIMA ASAKO, TETRAHEDRON LETT., 1981, 22, NO 8, 759-762
作者:SUDA MINORU、 FUKUSHIMA ASAKO
DOI:——
日期:——
Dichloromethylenation of esters and lactones by triphenylphosphine-carbon tetrachloride reagent
作者:Minoru Suda、Asako Fukushima
DOI:10.1016/0040-4039(81)80144-x
日期:1981.1
Catalytic reductive [4 + 1]-cycloadditions of vinylidenes and dienes
作者:You-Yun Zhou、Christopher Uyeda
DOI:10.1126/science.aau0364
日期:2019.2.22
Five-membered rings for two nickels The Diels-Alder reaction is widely used to make six-membered rings by adding four-carbon dienes to two-carbon alkenes. It would seem straightforward to likewise access five-membered rings from dienes and one-carbon sources, or carbenes, but that does not tend to work. Instead, the carbene adds to just half of the diene to form a cyclopropane. Zhou and Uyeda now show