Hurd-Mori 1,2,3-thiadiazole synthesis

What is Hurd-Mori 1,2,3-thiadiazole synthesis?

In a single, straightforward step, the Hurd-Mori 1,2,3-thiadiazole synthesis involves the reaction of thionyl chloride SOCl2 3 with N-acylated or tosylated hydrazone derivatives 1 or 2, leading to the formation of 1,2,3-thiadiazole 4.

Hurd-Mori 1,2,3-thiadiazole synthesis - general reaction scheme
Hurd-Mori 1,2,3-thiadiazole synthesis

R1 = OR, NH2

Typically, the reaction can be conducted between 0-60 ºC, with most of the reactions being carried out at room temperature. The reactivity of the hydrazones, when combined with either the acyl or tosyl leaving group with thionyl chloride, is substrate-dependent. However, while the acylated hydrazones tend to produce gaseous by-products, the reaction products of tosyl chloride must be separated from the reaction mixture.


On Acylhydrazones and 1,2,3-Thiadiazoles
Charles D. Hurd and Raymond I. Mori
Journal of the American Chemical Society 1955 77 (20), 5359-5364
DOI: 10.1021/ja01625a047