Pei Wei, Wei Han-Xun, Chen Dianjun, Headley Allan D, Li Guigen
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, USA.
J Org Chem. 2003 Oct 31;68(22):8404-8. doi: 10.1021/jo030193j.
N,N-dichloro-o-nitrobenzenesulfonamide (2-NsNCl2) was found to be an effective electrophilic nitrogen source for the direct diamination of alpha,beta-unsaturated ketones without the use of any metal catalysts. The reaction is very convenient to carry out without the protection of inert gases. Molecular sieves (4 A) and temperature were found to play key roles in controlling the formations of 3-trichloromethyl and dichloromethyl imidazoline products (16 examples). The 2-Ns-protection group of the resulting diamine products can be easily cleaved under mild Fukuyama's conditions. A new mechanism hypothesis of [2+3] cyclization and N-chlorination has been proposed to explain the product structures, particularly their regio- and stereochemistry.
发现N,N-二氯邻硝基苯磺酰胺（2-NsNCl₂）是一种有效的亲电氮源，可用于α,β-不饱和酮的直接双胺化反应，无需使用任何金属催化剂。该反应在不使用惰性气体保护的情况下非常便于进行。发现分子筛（4A）和温度在控制3-三氯甲基和二氯甲基咪唑啉产物的形成中起关键作用（16个实例）。所得双胺产物的2-Ns保护基团可在温和的福山条件下轻松裂解。提出了一种新的[2+3]环化和N-氯化机理假设来解释产物结构，特别是它们的区域和立体化学。
