Organic synthesis in water: Green protocol for the conjugate addition of thiols to p-quinones

The Michael addition of thiols to p-quinones proceeds efficiently in water at room temperature without a catalyst. Significant rate acceleration of this reaction is observed in water compared to organic solvents. Water played a dual role in simultaneously activating the quinones and thiols. This new methodology constitutes an easy, highly efficient and green synthesis of diaryl sulfides and aryl alkyl sulfides.

Thiols undergo smooth conjugate addition with p-quinones in water in the absence of a catalyst to produce 2-thia-1,4-hydroquinones in excellent yields. Figure optionsDownload as PowerPoint slide