Mn(III)-Based Oxidative Free-Radical Cyclizations of Unsaturated Ketones
作者:Bridget McCarthy Cole、Luning Han、Barry B. Snider
DOI:10.1021/jo961199u
日期:1996.1.1
free-radical cyclization of unsaturated ketones is a versatile synthetic procedure with broad applicability. For example, oxidation of cyclopentanone 1a with 2 equiv of Mn(OAc)(3).2H(2)O and 1 equiv of Cu(OAc)(2).H(2)O in AcOH at 80 degrees C for 1.5 h affords 75% of bicyclo[3.2.1]oct-3-en-8-one 8a and 15% of bicyclo[3.2.1]oct-2-en-8-one 9a. Bridgedbicyclicketones that cannot enolize further are isolated
Intramolecular reductive coupling reactions promoted by samarium diiodide
作者:Gary A. Molander、Caryn Kenny
DOI:10.1021/ja00203a027
日期:1989.10
Samariumdiiodide is a useful reagent for promoting intramolecular reductive coupling reactions, generating functionalized carbocycles. Ketone-olefin coupling, pinacolic coupling, and other related reductive coupling reactions are accomplished under mild conditions with samariumdiiodide. Products are accessed in high yield, and in many cases excellent stereochemical control is achieved at three contiguous
On the mechanism of the intramolecular samarium Barbier reaction. Probes for formation of radical and organosamarium intermediates
作者:Dennis P. Curran、Gu Xin、Wei Zhang、Paul Dowd
DOI:10.1016/s0040-4020(97)00608-x
日期:1997.7
A new type of mechanistic probe for the intramolecular samarium Barbier reaction has been designed, and two different probe substrates have been investigated in detail. Remarkably, no unambiguous evidence could be obtained in favor of any of the obvious intermediates (free alkyl or alkoxy radicals, ketyls, organosamarium species) that are postulated for this reaction. Several possibilities for modified mechanisms are suggested. (C) 1997 Elsevier Science Ltd.
MOLANDER, GARY A.;KENNY, CARYN, J. AMER. CHEM. SOC., 111,(1989) N1, C. 8236-8246