A metal-free CC bond cleavage reaction of β-nitrostyrenes in the presence of elemental sulfur and secondary amines/amides is described. Elemental sulfur serves as both a raw material and an oxidant for CC bond cleavage, and secondary amines or amides are both feasible nitrogen sources. Besides mild reaction condition and simple work-up procedure, the method provided thioamides with good to excellent
描述了在元素硫和仲胺/酰胺存在下 β-硝基苯乙烯的无金属 C C 键裂解反应。元素硫既是C C 键断裂的原料又是氧化剂,仲胺或酰胺都是可行的氮源。除了温和的反应条件和简单的后处理程序外,该方法还提供了具有良好收率的硫代酰胺。
Asymmetric Synthesis of 2,3,4-Trisubstituted Piperidines
Abstract Two different organocatalytic approaches for the asymmetricsynthesis of 2,3,4-trisubstituted piperidines were developed. Both approaches were based on an aza-Michael addition followed by cyclization and gave products in high enantiomeric excess. Two different organocatalytic approaches for the asymmetricsynthesis of 2,3,4-trisubstituted piperidines were developed. Both approaches were based
Substrate Promiscuity of <i>ortho</i>-Naphthoquinone Catalyst: Catalytic Aerobic Amine Oxidation Protocols to Deaminative Cross-Coupling and <i>N</i>-Nitrosation
作者:Tengda Si、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acscatal.9b03442
日期:2019.10.4
been identified as versatile aerobicoxidationcatalysts. Primary amines were readily cross-coupled with primary nitroalkanes via deaminative pathway to give nitroalkene derivatives in good to excellent yields. Secondary and tertiary amines were inert to ortho-naphthoquinone catalysts; however, secondary nitroalkanes were readily converted by ortho-naphthoquinone catalysts to the corresponding nitrite
First graphene oxide promoted metal-free nitrene insertion into olefins in water: towards facile synthesis of activated aziridines
作者:Prashant Shukla、Suhasini Mahata、Anjumala Sahu、Manorama Singh、Vijai K. Rai、Ankita Rai
DOI:10.1039/c7ra09351a
日期:——
A facile metal-free graphene oxide (GO)-catalyzedsynthesis of tosylaziridines using PhINTs as the nitrene source is reported. The reaction involves nitrene insertion into a variety of styrene/nitrostyrene derivatives in the presence of iodine at room temperature and in water. The envisaged process is highly green, operationally simple, it employs metal-free catalysis and it affords excellent yields
Threonine-derived thioureas as bifunctional organocatalysts for enantioselective Michael addition
作者:Zhi Zheng、Jian Lin、Yang Sun、Suoqin Zhang
DOI:10.1016/j.tetlet.2019.151382
日期:2020.1
A series of threonine-derived thioureas were developed through the facile modification of L-threonine chiral scaffold. The enantioselective efficiency were evaluated in the catalytic asymmetric Michaeladdition of 2-hydroxy-1,4-naphthoquinone to nitroalkenes, which afforded the chiral nitroalkylated naphthoquinone derivatives in high yields (up to 93%) and enantio-selectivities (up to 99% ee) under