Imidazolidin-2-thiones

Imidazolidine-2-thiones functionalised on the four-position can be obtained by reaction of HN(CH3)R with n-butyllithium, followed by addition of carbon disulfide. The lithium thicarbamate can then by further lithiated and cyclisation occurs upon reaction of this species with an imine (S) [22],... 

Ci3H15BrN204S l-(p-Bromophenyl)-L-glucofurano-[2,l-d]-imidazolidine-2- thione BGLFTT 37 389... 

Ci3Hi6N204S 1 -Phenyl-a-D-glucofurano-[2,1 -d ]-imidazolidine-2-thione PGFIMT 37 391... 

C14H18N2O5S l-Phenyl-(D-git/cero-L-g/uco-heptofurano)-[2,l-d]-imidazolidine-2-thione (PGHIMT10)87... 

The reaction of 2-aminobenzyl alcohol 376 with 2-chloro-4,5-dihydroimidazole afforded [2-(4,5-dihydro-177-imidazol-2-ylideneamino)phenyl]methanol hydrochloride 377, which upon treatment with carbon disulfide gave l-(477-3,l-benzoxazin-2-yl)imidazolidine-2-thione 378 (Scheme 71). The assumed reaction mechanism involved the initial formation of the dithiocarbamate 379, which underwent intramolecular nucleophilic addition to furnish the unstable thiazetidine 380. By nucleophilic attack of the hydroxy group on the carbon atom of the thiazetidine ring, thiocarbamate derivative 381 was formed, which gave the final 3,1-benzoxazine 378 by an intramolecular cyclocondensation with the evolution of H2S <2006H(68)687>. 

On being heated with acetic acid, imidazolidine-2-thiones of the type of 88 undergo rearrangement to the corresponding monocyclic 4-(tetrahydroxybutyl)imidazoline-2-thiones87-89 (89) these will be discussed in the next Section. 

These reorganization processes depend on small changes in the ligands. Reaction of [AuCN] and imidazolidine-2-thione (etu) leads to [Au(etu)(CN)] which crystallizes... 

Unsubstituted imidazolidine-2-thione, also known as ethylene thiourea, was one of the reported products (along with aniline, 2-anilino-2-imidazoline, and hydrogen sulfide) which resulted from thermolysis of 1-(2-aminoethyl)-3-phenyl-2-thiourea.31Cherbuliez etal.32 found that l,3-diarylimidazolidine-2-thiones (20) were formed by treatment of the l,3-diaryl-l-(2-hydroxyethyl)-2-thioureas (19) with concentrated hydrochloric acid. 

P Bottomley, RA Hoodless, NA Smart. Review of methods for the determination of ethylenethiourea (imidazolidine-2-thione) residues. Residue Reviews 95 45-84, 1985. 

FIGURE 3. Thiocarbonyl ligands involved in Tables 20-25 (a) pyridine-2-thione, (b) pyridine-4-thione, (c) pyrimidine-2-thione, (d) l,3-imidazoline-2-thione, (e) benz-l,3-imidazoline-2-thione, (f) l,3-imidazolidine-2-thione, (g) l,3-thiazoline-2-thione, (h) benz-1,3-thiazoline-2-thione, (i) 1,3-thiazolidine-2-thione, (j) 1,2,4-triazoline-3(5)-thione, (k) 1,2,3,4-tetrazoline-5-thione... 

There have been investigations of the reaction of cyclic thioureas with unsaturated carbonyls. For example, interactions involving imidazolidine-2-thione 64 (n = 1) or tetrahydropyrimidine-2-thione 64 (n = 2) with ketones 65 (k = 1-3) in the presence of the catalyst boron trifluoroetherate yielded only one stereoisomer 66 according to Perjesi et al. [70] (Scheme 3.20). 

Ethvlenethiourea (2-mercaptoimidazolinej imidazolidine-2-thione imidazoline-2-thiol, VIII) is a water-soluble white crystalline solid used extensively in curing elastomers (rubbers, e.g., polychloroprenes, polyacrylates, etc.) It is also present as an impurity in the ethylene bisdithiocarbamates widely used as fungicides. When the fungicides are present as a contaminant in heated foods, they may be converted to the ethylenethiourea (ref. 

Heteropentalene structures 4 were synthesized by the reaction of imidazolidine-2-thione with ArNCS in the presence of BuLi followed by oxidation of intermediates 130 with Br2/NaHCC>3 (Scheme 37) <1997BCJ1267>. 

Imidazoline-2-thiones and imidazolidine-2-thiones react with 1,2-dibromoethane in the presence of aqueous sodium hydroxide and a charge transfer catalyst (CTC), or with a-cyanobenzyl benzenesulfonate, to give the corresponding imidazo[3,l-f>]thiazoles (equation 10) (80JHC393, 61JOC2715). In an analogous reaction, the condensation of 5,5-diphenyl-2-thiohydantoin with ethylene dibromide yielded two isomeric products, (99 major) and (100 minor) (8lJCS(P2)789). 

For the imidazolidine-2-thiones, which have received the most extensive study in this class of complexes, the monosubstituted imidazolidines stabilize osmium(III) while the disubstituted ones stabilize osmium(IV) and osmium(VI).714... 

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