In accord with the Hurd-Mori reaction conditions, 1- or 2-phosphonyl hydraz
ones reacted with thionyl chloride to afford 4- or 5-phosphonyl 1,2,3-thiad
iazoles in good yields and purity. A synthesis of 1- or 2-phosphonyl hydraz
ones using two methods is described. (C) 2000 John Wiley & Sons, Inc.