Cyclopropenylcarbinol Derivatives as New Versatile Intermediates in Organic Synthesis: Application to the Formation of Enantiomerically Pure Alkylidenecyclopropane Derivatives
作者:Samah Simaan、Ahmad Masarwa、Elinor Zohar、Amnon Stanger、Philippe Bertus、Ilan Marek
DOI:10.1002/chem.200901074
日期:2009.8.24
The copper‐catalyzed carbomagnesiation (or hydrometalation) reaction of chiralcyclopropenylcarbinolderivatives, obtained by means of a kinetic resolution of secondary allylic alcohols, leads to an easy and straightforward preparation of enantiomericallypurealkylidenecyclopropanederivatives. The reaction mechanism is composed of a syn‐carbometalation followed by a syn‐elimination reaction. To gain
Regioselective Carbon–Carbon Bond Cleavage in the Oxidation of Cyclopropenylcarbinols
作者:Ahmad Basheer、Masaaki Mishima、Ilan Marek
DOI:10.1021/ol201581c
日期:2011.8.5
The strained double bond of cyclopropenylcarbinols undergoes a facile oxidation reaction to lead to unsaturated carbonyl derivatives. The distribution of the formed products depends on the relative stability of carbon-centered radical species, and the Sharpless kinetic resolution leads to enantiomerically pure Baylis–Hillman enal adducts.
Highly diastereoselective approach to methylenecyclopropanes via boron-homologation/allylboration sequences
作者:A. N. Baumann、A. Music、K. Karaghiosoff、D. Didier
DOI:10.1039/c5cc09904h
日期:——
A simple and efficient diastereoselective synthesis of methylenecyclopropanes is described, in which boron-homologation and allylboration are merged into a one-pot process, starting from in-situ generated cyclopropenyllithium species. This unprecedented methodology...
Synthesis of Nitrogen-Substituted Methylenecyclopropanes by Strain-Driven Overman Rearrangement of Cyclopropenylmethyl Trichloroacetimidates
作者:James K. Howard、Chintan Amin、Brendan Lainhart、Jason A. Smith、Jack Rimington、Christopher J. T. Hyland
DOI:10.1021/jo501423u
日期:2014.9.5
Nitrogen-substituted methylenecyclopropanes have been prepared by a strain-driven Overman rearrangement of cyclopropenylmethyl trichloroacetimidates. The reaction proceeds at room temperature and without the need of a transition-metal catalyst. Furthermore, it has been shown that C-3-substituted cyclopropenylmethyl trichloroacetimidates undergo a hydrolytic ring-opening reaction to form allenylcarbinols
Stereocontrolled approaches to 2-(2-aminoalkyl)-1-hydroxycyclopropanes
作者:Mark S Baird、Florian A.M Huber、William Clegg
DOI:10.1016/s0040-4020(01)00996-6
日期:2001.12
(1S,2S)-2[(S)-Amino(4-methoxyphenyl)methyl]cyclopropan-1-of together with a range of racemic 2-(2-aminoalkyl)-1-hydroxy-cyclopropanes were prepared by a stepwise procedure involving a 1,3-dipolar cycloaddition of a nitrile oxide to a cyclopropene followed by reduction of the derived bicycle. (C) 2001 Elsevier Science Ltd. All rights reserved.