Integrated process for the preparation of 2-dialkoxyphosphinylimino-1,3-dithietane

摘要

There is provided a fully integrated process for preparing a 2-dialkoxyphosphinylimino-1,3-dithietane in good overall yields with considerable savings in materials, time and labor involving a plurality of steps comprising the overall reaction of a dialkoxyphosphoryl chloride and an alkali metal- or ammonium thiocyanate to obtain a dialkoxyphosphinyl isothiocyanate, reacting the latter with 1.1 to 1.2 molar equivalents of an alkali mercaptan in the presence of a water and, finally, reacting resultant dialkoxyphosphinyldithiocarbamate with methylene bromide or methylene iodide in the presence or absence of a non-ionic surfactant under controlled pH conditions ranging from 5 to 8 to obtain resultant 2-dialkoxyphosphinylimino-1,3-dithietane. The latter finds utility for the control of root-knot nematode.