K₂S₂O₈-Promoted Aryl Thioamides Synthesis from Aryl Aldehydes Using Thiourea as the Sulfur Source.

Yongjun Bian,Xingyu Qu,Yongqiang Chen,Jun Li,Leng Liu

doi:10.3390/molecules23092225

Abstract

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.

Highlights

The synthesis of sulfur-containing organic compounds has received much attention in recent years, due to their wide applications in biology, chemistry, and materials science [1,2,3,4,5,6,7,8,9,10]
Jiang et al [35] reported that sodium sulfide as a sulfur source was applied for the synthesis of thioamides using aldehydes and N-substituted formamides
A coupling reaction between quaternary ammoniums, N-substituted formamides, and sodium disulfide was accomplished for rapid access to aryl thioamides [36]

Summary

Introduction

The synthesis of sulfur-containing organic compounds has received much attention in recent years, due to their wide applications in biology, chemistry, and materials science [1,2,3,4,5,6,7,8,9,10]. There are many sulfur reagents for their synthesis, such as P2 S5 [11], Lawesson’s reagent [12], disulfides [13,14,15], thiols [16,17,18,19], sulfonyl hydrazides [20,21,22,23], sodium sulfonate [24,25,26,27,28], and elemental sulfur [29,30,31,32] Among them, both P2 S5 and Lawesson’s reagent are the most widely used reagents, and yet they have an obvious drawback of being sensitive to moisture. Jiang et al [35] reported that sodium sulfide as a sulfur source was applied for the synthesis of thioamides using aldehydes and N-substituted formamides. We want to report a new three-component coupling reaction between aryl aldehydes, thiourea as an effective sulfur source, and DMF or DMAC, for the synthesis of various aryl thioamides

Results and Discussion

Methods

Conclusions