Efficient Synthesis of Esters by Cleavage of C–S and C–N Bonds via Alkylation and Activation of Thioamides
摘要:
A mild and efficient reaction for synthesizing esters from thioamide precursors has been established. This method is accomplished in one pot under mild conditions. The process involves the alkylation and activation of inert thioamides, which leads to the cleavage of stable C–N and C–S bonds, eventually resulting in valuable esters with a broad range of substrates. The transformation can be easily carried out at room temperature using thioamide substrates, reactants, and activating agents. This protocol has been demonstrated by synthesizing important esters with applications.
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。
Aqueous Compatible Protocol to Both Alkyl and Aryl Thioamide Synthesis
作者:Jianpeng Wei、Yiming Li、Xuefeng Jiang
DOI:10.1021/acs.orglett.5b03541
日期:2016.1.15
An efficient aqueous synthesis of thioamides through aldehydes, sodium sulfide, and N-substituted formamides has been developed. Both alkyl and aryl aldehydes are amenable to this protocol. N-Substituted formamides are essential for this transformation. Readily available inorganic salt (sodium sulfide) serves as the sulfur source in water, which makes this method much more practical and efficient.
A general method for one-potsynthesis of thioamides without transition metals or external oxidants is developed through a three-component reaction involving chlorohydrocarbon, amide and elementalsulfur. Both alkyl and aryl thioamides could be obtained in moderate to excellent yields through this protocol. A high tolerance regarding various substituents on chlorohydrocarbon or amide was justified
K2S2O8-Promoted Aryl Thioamides Synthesis from Aryl Aldehydes Using Thiourea as the Sulfur Source
作者:Yongjun Bian、Xingyu Qu、Yongqiang Chen、Jun Li、Leng Liu
DOI:10.3390/molecules23092225
日期:——
Thiourea as a sulfur atom transfer reagent was applied for the synthesis of aryl thioamides through a three-component coupling reaction with aryl aldehydes and N,N-dimethylformamide (DMF) or N,N-dimethylacetamide (DMAC). The reaction could tolerate various functional groups and gave moderate to good yields of desired products under the transition-metal-free condition.