Organic Chemistry Portal

Abstracts

Search:

Sulfuryl Fluoride Promoted Thiocyanation of Alcohols: A Practical Method for Preparing Thiocyanates

Guofu Zhang, Lidi Xuan, Yiyong Zhao, Chengrong Ding*

*College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, P. R. of China, Email: dingcrzjut.edu.cn

G. Zhang, L. Xuan, Y. Zhao, C. Ding, Synlett, 2020, 31, 1413-1417.

DOI: 10.1055/s-0040-1707151



see article for more reactions

Abstract

SO2F2 promotes a one-step synthesis of thiocyanates through C-O bond cleavage of readily available alcohols with ammonium thiocyanate as the thiocyanating agent. A borad range of alcohols reacted with high efficiency in ethyl acetate under mild conditions to afford the corresponding thiocyanates in very good yields with broad functional group compatibility.

see article for more examples



Details

The document details a novel method for synthesizing thiocyanates from alcohols using sulfuryl fluoride (SO2F2) and ammonium thiocyanate (NH4SCN). This method, developed by researchers at Zhejiang University of Technology, avoids the need for additional catalysts and operates under mild conditions at room temperature. The process is highly efficient, offering yields up to 98% and demonstrating good functional-group compatibility. The optimal conditions involve using Na2CO3 as a base and ethyl acetate as a solvent, with the reaction proceeding under an SO2F2 atmosphere for five hours. This method is applicable to a wide range of alcohols, including benzylic, heteroarylmethanols, and aliphatic alcohols, producing the corresponding thiocyanates in good to excellent yields. The method's practicality is further demonstrated by its scalability, successfully synthesizing methyl 4-(thiocyanatomethyl)benzoate on a gram scale with a 96% yield. This efficient and economical approach is significant for organic synthesis, particularly in pharmaceuticals, dyes, natural products, and agrochemicals. The research was supported by the National Natural Science Foundation of China and the Natural Science Foundation of Zhejiang Province.


Note

Care is required in performing chemistry in which SO2F2 is employed. Although SO2F2 is a colorless, odorless gas that is not immediately irritating to the eyes or skin, it is a broad-spectrum biocide at high concentrations or prolonged exposures and should only be handled with adequate ventilation. Furthermore, repeated exposure to high levels of sulfuryl fluoride may cause lung and kidney damage.


Key Words

sulfuryl fluoride catalysis, alcohols, thiocyanation, ammonium thiocyanate, thiocyanates


ID: J72-Y2020