Electrophilic Diamination of Alkenes by Using FeCl<sub>3</sub>−PPh<sub>3</sub> Complex as the Catalyst
作者:Han-Xun Wei、Sun Hee Kim、Guigen Li
DOI:10.1021/jo0200769
日期:2002.7.1
electrophilic diamination reaction of electron-deficient alkenes. Improvements on yields and stereoselectivity have been achieved for both alpha,beta-unsaturated carboxylic esters and ketones. Under the new catalytic system, alpha,beta-unsaturated carboxylic esters were found to be superior to their ketone counterparts, which is opposite to the previous (C(3)F(7)CO(2))(2)Rh](2)-catalyzeddiamination. The reaction
The Combination of TsNH2 and NCS as Nitrogen and Chlorine Sources for Direct Diamination of Enones
作者:Cody Timmons、Dianjun Chen、Xin Xu、Guigen Li
DOI:10.1002/ejoc.200300326
日期:2003.10
observation of any haloamines. The reaction employs the readily available inexpensive combination of NCS and TsNH2 as an electrophilic nitrogen source, and three nitriles as nucleophilic nitrogen sources. A novel mechanism involving the formation of aziridinium intermediates from the reaction of TsNHCl with olefins and a new [2+3] cyclicaddition for aziridinim ring opening has been proposed for the
Direct Electrophilic Diamination of Functionalized Alkenes without the Use of Any Metal Catalysts
作者:Dianjun Chen、Cody Timmons、Han-Xun Wei、Guigen Li
DOI:10.1021/jo030098a
日期:2003.7.1
A new direct electrophilic diamination reaction of alpha,beta-unsaturated ketones and esters has been established without the use of any metal catalysts. Three types of nitriles (CH3CN, CH3CH2CN, and CH3CH2CH2CN) were employed as nucleophilic nitrogen sources. A new mechanism has also been proposed to explain the resulting regio- and stereoselectivity.
Organocatalyzed regio- and stereoselective diamination of functionalized alkenes
作者:Hui Wu、Xiaoyun Ji、Hao Sun、Guanghui An、Jianlin Han、Guigen Li、Yi Pan
DOI:10.1016/j.tet.2010.04.054
日期:2010.6
The first organocatalyzed diamination reaction of alkenes with N,N-dichlorotoluenesulfonamide (TsNCl2) and acetonitrile as nitrogen sources was reported. The catalytic diamination reaction was convenient to carry out, resulting in imidazoline products with good yields and excellent regio- and stereoselectivities. Several other organic molecules were also tried as catalyst for this reaction and good results were achieved. A new one-pot synthesis of vicinal diamines via the current PPh3-catalyzed diamination and the hydrolysis of resulting imidazoline products with SnCl4 as promoter was also established. (C) 2010 Elsevier Ltd. All rights reserved.
A Novel Electrophilic Diamination Reaction of Alkenes
作者:Guigen Li、Han-Xun Wei、Sun Hee Kim、Michael D. Carducci
A three-component electrophilicreaction transforms olefins into imidazoline and diamine derivatives. Rhodium(II) heptafluorobutyrate dimer (2 mol %) was utilized as the catalyst and N,N-dichloro-p-toluenesulfonamide (TsNCl2 ) and acetonitrile as the nitrogen sources. Modest to good yields (45-82 %) and high regio- and stereoselectivity were achieved.