27464-82-0Relevant articles and documents
Studies on organophosphorus compounds XLIX. An improved method for the preparation of 2,5-disubstituted 1,3,4-thiadiazoles and 1,3,4-thiadiazole-2(3H)-thiones
Rasmussen, P.B.,Pedersen, U.,Thomsen, I.,Yde, B.,Lawesson, S.O.
, p. 62 - 65 (2007/10/02)
The reaction of 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (LR) with N,N'-diacylhydrazines and N-acyl-N'-ethoxycarbonyl hydrazines has been investigated.It is shown that 2,5-disubstituted-1,3,4-thiadiazoles and 5-phenyl-1,3,4-thiadiazole-2(3H)-thione are produced in good yields.However, in the case of N-acetyl-N'-ethoxycarbonylhydrazine a 2,3-dihydro-1,3,4,2-thiadiazaphosphole, X, is formed.The fragmentation patterns in the mass spectra of simple 2,5-disubstituted 1,3,4,-thiadiazoles, IIIa-f, are described.
New Syntheses with Elemental Sulfur. - Synthesis and Reactions of New 1,3,4-Thiadiazoles
Hagen, Helmut,Kohler, Rolf-Dieter,Fleig, Helmut
, p. 1216 - 1231 (2007/10/02)
The one-step synthesis of 2,5-dialkyl-1,3,4-thiadiazoles 1 from aliphatic aldehydes, hydrazine hydrate and elemental sulfur is described.Chlorination of 1a yields 2,5-bis(trichloromethyl)-1,3,4-thiadiazole (2a).Reaction of 2a with methanol affords the orthoester 3, which forms with aromatic compounds a large number of new 2,5-disubstituted 1,3,4-thiadiazoles 5 - 7.Removal of one trichloromethyl group of 2a leads to 2-trichloromethyl-1,3,4-thiadiazole (10) which on halogenation gives the 2-halo-5-trichloromethyl-1,3,4-thiadiazoles 11.Reactions with nucleophilic compounds lead to the corresponding thiadiazoles 12 and 13.
