开发了一种通过MAD / n - Bu 4 NI介导的单活化MCP扩环制备官能化亚烷基吡咯烷的新颖合成途径。发现该反应的底物范围对于多种醛亚胺而言是宽泛的,并且对称地以及非对称地单活化的MCP以良好的产率(高达92%)产生相应的五元杂环化合物。该方法是对以前有关MCP环扩环的报告的补充,该报告显示,只需改变催化剂体系,就可以从同一MCP中实现不同杂环骨架的选择性合成。
Deamination of Methylenecyclopropylcarbinylamine. The Formation of a Vinyl Cation by Carbon-Carbon Bond Cleavage
作者:Akio Nishimura、Masaki Ohta、Hiroshi Kato
DOI:10.1246/bcsj.43.1530
日期:1970.5
3-methylenecyclobutanol. On the basis of these results and the deuterium distribution of the deamination products of methylenecyclopropylcarbinylamine-α,α-d2, the homoallylic (III) and cyclopropylvinyl (VIII) cations are proposed as intermediates.
Synthesis of Highly Functionalized Pyrrolidines via a Selective Iodide-Mediated Ring Expansion of Methylenecyclopropyl Amides
作者:Mark E. Scott、Mark Lautens
DOI:10.1021/jo802049u
日期:2008.11.7
iodide-mediated, tandem Mannich/cyclization to afford trans-2,3-disubstituted pyrrolidines from methylenecyclopropyl amides in good to excellent yields and selectivities. The reaction scope has been drastically expanded to include a wide array of aromatic, heteroaromatic and alpha,beta-unsaturated imines, as well as a variety of methylenecyclopropyl amides. Additionally, mechanistic studies were carried out
Generation of diazo-2-methylenecyclopropane and its 1,3-dipolar cycloaddition to acrylates
作者:Yu. V. Tomilov、I. P. Klimenko、E. V. Shulishov、O. M. Nefedov
DOI:10.1007/bf02495762
日期:2000.7
N-(2-Methylenecyclopropyl)-N-nitrosourea (2) was synthesized for the first time (yield 70%) and its decomposition induced by bases was studied. In particular, treatment with MeONa/MeOH at -30 degrees C in the presence of methyl methacrylate gives the corresponding 1-pyrazoline stereoisomers, the products of [3+2]-cycloaddition of diazo-2-methylene-cyclopropane (1) generated in situ. Decomposition of 2 on treatment with K2CO3 at 0-5 degrees C in the presence of acrylonitrile also proceeds as [3+2]-cycloaddition; however, the expected 2-pyrazoline easily isomerizes into 5(3)-isopropenyl-3(5)-cyanopyrazole. Buta-1,2,3-triene is the main product of base-induced decomposition of 2 in the absence of unsaturated substrates.