2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson’s Reagent, LR, 1) reacts with cycloalkylidenecyanoth
ioacetamides (2 and 3) to give 5�-cyano-2�-(4-methoxyphenyl)spiro [cyclopentane(cyclohexane)-1,6� -perhydro-[1,3,2]thiazaphosphixane]
2� ,4� -disulfide (4 and 5). The reaction of compounds 4 and 5 with �-halo compounds led to the formation of the substituted thio-compounds 6a–e and 7a–e, respectively, these compounds, upon treatment with sodium ethoxide, produce the corresponding thienothiazaphosphixine derivatives 8a–e and 9a–e respectively. Compounds 8a–e and 9a–e react with LR under different reaction conditions to give polyfused heterocyclic compounds 10a–d and 11a–d respectively. Treatment of compounds 8b and 9b with CS2 and (CH3)2SO4 gave the correspond
ing dithiocarbamate methyl ester derivatives 12 and 13, respectively, which on treating with hydrazine hydrate yielded compounds 14 and 15 respectively. Compounds 14 and 15 reacted with LR to yield compounds 16a,b and 17a,b respectively.