Synthesis and properties of benzo[b]thiopheno[2,3-d]-1,3,2λ5-diazaphosphinane-2-thione derivatives

A Berzelius Reagent, Phosphorus Decasulfide (P4S10), in Organic Syntheses

“…The reaction of the amides 166 with P 4 S 10 gave the addition products 168 through the intermediate 167 , which has an o -amino system (Scheme ) . Similar results were observed with 2-amino-3-carbamoyltetrahydrobenzothiophene 169 and 2-aminobenzamide 170 , which gave the addition products tetrahydrobenzothiophenodiazaphosphinane-2-thion-4-one 171 and benzodiazaphosphorine-2,4-dithione 172 , − respectively, the structure of which were described by X-ray crystallography …”

“…The reaction of the amides 166 with P 4 S 10 gave the addition products 168 through the intermediate 167, which has an o-amino system (Scheme 45). 232 phosphorine-2,4-dithione 172, [233][234][235] respectively, the structure of which were described by X-ray crystallography. 236 A similar reaction, addition of part of P 4 S 10 , was reported as minor products of the reaction of N-(pyridine-2-yl)arylcarbomades with P 4 S 10 (Table 7, entry 27), which yielded 173.…”

Synthesis of new heterocyclic system of 4,5,7,8‐tetrahydroimidazo[1,2‐c][1,3]thiazolo [4,5‐e][1,3,2]diazaphosphinine starting from 2‐aroylamino‐3,3‐dichloroacrylonitrile

“…On reacting with hydrogen sulfide in pyridine, nitriles 2a-c were converted almost quantitatively to corresponding thioamides 3, which were then treated with 2 equiv of P 2 S 5 in pyridine by the known procedure [17][18][19][20] to furnish substituted derivatives 4 of 4,5,7,8-tetrahydroimidazo[1,2c] [1,3]thiazolo [4,5-e] [1,3,2]diazaphosphinine, a novel-fused heterocyclic system. As found, compounds 4 are also obtainable directly from 2 by treating with phosphorus pentasulfide.…”

The Reaction of Phosphorus Decasulfide with some Hydrazides and their Hydrazones: New Route for Construction of Four‐membered, Five‐membered, and Six‐membered Phosphorus Heterocycles

“…Phosphorus decasulfide P 4 S 10 (also called phosphorus pentasulfide P 2 S 5 ) is a very important starting material for the synthesis of many linear phosphorus and sulfur compounds but has been used less extensively for the preparation of cyclic compounds containing the exocyclic PS 2 group . Limited heterocyclic compounds containing the exocyclic PS 2 group were prepared by reactions of phosphorus decasulfide with amide systems having reactive group at ortho position such as anthranilamide , 2‐amino‐3‐carbamoyl‐4,5,6,7‐tetrahydrobenzo[ b ]thiophene , N , N ‐diphenylurea , 1,2‐trimethylene‐4‐amino‐5‐cyanoimidazole , 3‐methyl‐4‐carbamoyl‐5‐aminopyrazole , and N ‐[cyano(imidazolidin‐2‐ylidene)methyl]carboxamide . Phosphorus heterocycles are of potential interest as anti‐inflammatory, herbicides, insecticides, and fungicides .…”