ChemInform Abstract: Thionations Using a P₄S₁₀—Pyridine Complex in Solvents such as Acetonitrile and Dimethyl Sulfone.

Abstract

Thionations Using a P 4 S 10 -Pyridine Complex in Solvents such as Acetonitrile and Dimethyl Sulfone. -The compound (II) is an efficient thionation reagent which exhibits good solubility and thermal stability and allows formation of a wide range of thiones. -(BERGMAN*, J.; PETTERSSON, B.; HASIMBEGOVIC, V.; SVENSSON, P. H.; J. Org. Chem. 76 (2011) 6, 1546-1553, http://dx.doi.org/10.1021/jo101865y ; Unit Org. Chem., Dep. Biosci. Nutr., Karolinska Inst., S-141 57 Huddinge, Swed.; Eng.) -Jannicke 24-039

A Purification-Free Method for the Synthesis of Thiazolium Salts Using P2S5-Py2 Complex or P4S10

“…In terms of practical applications, the use of Lawesson's reagent requires very specific reaction conditions and necessitates purification via chromatography, whereas P4S10 is poorly soluble in many solvents. In recent years combinations of reagents have been reported, such as P4S10/HMDO, 13 P4S10/Al2O3, 14 and, P2S5-Py2 (14), 15 which often result in better yields than using Lawesson's reagent or P4S10 alone.…”

“…Although P2S5-Py2 is a common thionating reagent, it is not commercially available; it can be obtained by refluxing P4S10 in dry pyridine. 15 The primary advantage of the P2S5-Py2 reagent is its stability to higher temperatures (up to 180 °C). This feature is desirable as we envisioned the thionated intermediate obtained from 9 would cyclize with heating, thereby yielding thiazolium 11 in a one-pot method.…”