Amines dithiocarbamate synthesis

Carbon disulfide is the starting point for dithiocarbamate synthesis via reaction with an amine... 

Considerably less is known about the chemistry of palladium and platinum 1,1-dithio complexes. Of late, there has been only one report that dealt with the synthesis of a large number of palladium dithiocar-bamates 392). Twenty-five yellow palladium dithiocarbamate complexes were obtained by reaction of PdCla with NaR2dtc in methanol solution. Several other reports have appeared in which a few dithiocarbamate complexes of palladium were synthesized. Thus, the novel [Pd (OH)2dtc 2], which is soluble in water, was isolated 393). The synthesis of optically active palladium(II) complexes of AT-alkyl-a-phen-ethyldithiocarbamates, similar to (XXIV), via the reaction between the optically active amine, CS2, and PdCl2, has been described. From ORD and CD spectra, it has been established that the vicinal contribution of a remote, asymmetric carbon center could give rise to optical activity of the d—d transitions of palladium 394). Carbon disulfide has been shown to insert into the Pt-F bond of [PtF(PPh3)3]HF2, and X-ray studies indicated the structure (XXIX). 

Bardaji, M Laguna, A., Laguna, M. and Merchan, F. (1994) Methyl dithiocarbamate gold(l) and gold(lll) complexes. Synthesis and reactivity with amines. Inorganica Chimica Acta, 215 (1-2), 215-218. 

Craig and co-workers247 reported the synthesis of l-aza-2,4,10-trithiaada-mantane (227) as a by-product in the reaction of ammonium dithiocarbamate with an aqueous solution of chloroacetaldehyde. The same compound is reported to be obtained by the reaction of mercaptoacetaldehyde with ammonia248 and then by the reaction of tri(2,2-bis(ethoxy)ethyl]amine (228) with hydrogen sulfide in the presence of hydrobromic acid.249 The... 

N-Bis(methylthio)methylene derivatives of amines (iminodithiocarbonates) were first introduced by Hoppe and Beckmann468 for the synthesis of a-amino acids from glycine. The A bis(methylthio)methyleneamines are prepared by reaction of a primary amine with carbon disulfide (HAZARD) in the presence of triethylamine and iodomethane to form a methyl dithiocarbamate derivative, which is then S-alkylated with a second equivalent of iodomethane in the presence of potassium carbonate as the base. Scheme 8,233 illustrates an alternative one pot procedure applied to the synthesis of /erf-butyl N-[bis(methylthio)-methylene]glycinate and its use in diastereoselective conjugate addition under... 

The cobalt complex, Co(NO)[S2CN(CH3)2]2, is well characterized. - However, direct synthesis of itfrom the reaction between NO and Co[S2CN(CH3)2]2 leads to impure materials which are very difficult to purify. The ethylenedi-amine complex, Co(NO)(C2H4N2H4)2(Cl04)2, can readily be prepared in good yields and is easily converted into the dithiocarbamate derivative. The products from these reactions are obtained in a relatively pure form and can easily be further purified. 

These are easily prepared by the reaction of amines with carbon disulfide (1) in the presence of alkali (Scheme 17).2 The synthesis of dithiocarba mates (4) was first reported by Debus in 1850. Dithiocarba mates (4) form metal chelates, and sodium dimethyl dithiocarbamate is used in quantitative inorganic analysis for the estimation of metals, e.g. copper and zinc. Dithiocarba mates are also employed as vulcanisation accelerators and antioxidants in the rubber industry, and as agricultural fungicides.3 The parent dithiocarbamic acids are unstable, decomposing to thiocyanic acid and hydrogen sulfide however, the salts and esters are stable compounds. Dithiocarba mates (4) are oxidised by mild oxidants to the thiuram disulfides (38) (Scheme 17). 

Dithiocarbamic acids, R2NC(S)SH, are rather unstable and seldom isolated or used as such. Usually their alkali metal or (substituted) ammonium salts are prepared for further use as starting materials in the synthesis of various metal complexes or organometallic derivatives. The most common is the reaction of primary or secondary amines with carbon disulfide in alkaline medium. 

A one-pot solvent and catalyst free reaction of amine, CS2 and alkyl halides at room temperature presents a very simple and green route to the synthesis of dithiocarbamates (Scheme 5.49). Significantly, higher yields were obtained in neat compared to those in organic solvents.Certainly, this procedure is of much importance in pharmaceutical and agrochemical industries. 

Synthesis of Dithiocarbamates from CSj. The addition of ammonia or alkylamines to CS2 to form the amine salts of dithiocarbamic acids is analogous to their addition to CO2 to form the corresponding carbamate salts. 

Both ( )- and (Z)-allyl dithiocarbamates have been stereoselectively prepared in high yields from acetates of MBH adduets in catalyst-free one-pot three-component coupling reactions of carbon disulfide and amine in water under a mild and green procedure (Scheme 3.152). The reaction pathway involves the nucleophilic displacement (-S n2 ) of MBH acetates by dithio-carbamate anions. The utility of these allyl dithiocarbamates has been demonstrated in the synthesis of 3,5-dibenzyl-l,3-thiazines derivatives 344 and 345 (Scheme 3.153). ... 

Subsequently, a one-pot three-component highly stereoselective synthesis of hitherto unknown trisubstituted ( )- and (Z)-allyl dithiocarbamates 831 and 832 in water at room temperature without using a catalyst was disclosed (Scheme 4.241). This one-pot procedure was performed simply by stirring a mixture of an amine, CS2, and an acetate of acrylonitrile/acrylate ester-derived MBH adduct in water at room temperature for 6-10 h to afford the corresponding allyl dithiocarbamates 831 and 832 in 83-94% yields along with... 

The addition reaction between amines and carbon disulphide has attracted the attention of several research groups because it constitutes a common route to dithiocarbamates. In their latest paper, Fitton and his co-workers, by means of cross-over experiments and the application of optically labelled bases, have further established that the reaction of benzylic, tertiary amines with carbon disulphide proceeds by an inter-molecular addition-elimination-recombination mechanism. On the other hand, Kreutzkamp and his co-workers claim that the insertion reaction of carbon disulphide with tertiary Mannich bases proceeds by an intramolecular mechanism. The synthesis of thiazolidine-2-thiones by the insertion reaction of carbon disulphide with aziridines has been the subject of two recent papers. - One of these deals mainly with the mechanistic and stereochemical aspects of this reaction, which was studied using 2-substituted and cis- and rra/z5 -2,3-disubstituted aziridines as reactants. A mechanism accounting for the stereoselectivity of the reaction has been drawn up by the authors (Scheme 7). 

Modem legislation puts much emphasis on the prevention of the formation of carcinogenic secondary iV-nitrosamines as by-products of sulfur vulcanization (30). This limits the choice of possible accelerators to those which have no secondary amine groups embedded in their chemical stmcture or may contain residual secondary amines dating back to their synthesis usually the ultra-accelerators mentioned above. In such cases it is extra difficult to develop a proper vulcanization system. New ultra-accelerator systems like dibenzyl dithiocarbamate or tetrabenzyl thiuramdisulfide may be used in such cases, where the dibenzylamine embedded in these compoimds is an exception in that it does not generate N-nitrosamines carcinogenic to human beings (31). 

The aliphatic amines are valuable intermediates for chemical synthesis applications, Reaction of ethylamine with cyanuric chloride yields triazine-type herbicides, Diethylamine is used in the preparation of vulcanization accelerators where reaction with carbon disulfide yields a dithiocarbamate. Triethyl-amine is used as an acid acceptor in chemical syntheses and as a salt former in various purification processes. The amine is used as a corrosion inhibitor in aqueous systems, as a catalyst in polyurethane applications, in textile and photographic applications, and in anodic electrocoating. 

CS2 as a type of liquid sulfur source was applied in benzothiazole synthesis as well. In 2011, Ma and co-workers found that copper salt can catalyse the reaction between 2-haloanilines and dithiocarbamate, which was generated in situ from amines and carbon disulfide (Scheme 2.145a). ° 2-N-Substi-tuted benzothiazoles were produced in good yields. Later on, they found that thiols can be applied as well. Condensation of carbon disulfide with thiols in... 

Recently, Ma et al. developed a three-component reaction for the synthesis of 2-A -substituted benzothiazoles 107 via the copper-catalyzed coupling of 2-iodoanilines, carbon disulfide, and secondary amines (Scheme 3.56) [149]. In these reactions, the condensation of CS with an amine in the presence of a base generates dithiocarbamate salts XXXV, which undergo coupling with 2-iodoanilines to give XXXVI and subsequent intramolecular condensation and elimination to afford the substituted benzothiazoles 107. 

In the same manuscript, the authors described the synthesis of polyfunctionalized Z-dithiocarbamates 61, which are important building blocks due to their numerous biological activities [59]. This 6-MCR proceeded through a one-pot and six-component Ugi/nucleophilic addition sequence in high yields (Scheme 7.25). The main difference with the aforementioned 5-MCR was the use of carbon disulfide and an amine for the nucleophilic addition. 

Synthesis of Thiolcarbamates Via the Reaction of Sodium or Trlethyl-amine Salts of Disubstituted Dithiocarbamic Acids with 4 Chloro 3>5-dlnitrobenzotrifluoride. 

A facile synthesis of 2,3,5-tri-O-acetyl-p-D-ribofuranosyl isothiocyanate fiom the corresponding ribosyl chloride has been detailed. 2,3,4,6-Tetia-D-acetyl- 3-D-glucopyianosyl isothiocyanate continues to be a popular reagent for preparing diastereomeric thiourea or dithiocarbamate derivatives in the reversed-phase resolution of enantiomeric amine- or thiol-... 

The bis(2,2,2-triiluoroethyl) dithiocarbamate salt, NaS2CN(CH2CF3)2, is a valuable precursor to a range of complexes that find widespread uses in analytical chemistry (74-82). It can be readily prepared from the amine using sodium amide as the base in the presence of carbon disulfide (Eq. 5) (76, 75), and a synthesis of the lithium salt has also been reported (83, 84). 

In a series of papers, Siddiqi et al. detail the synthesis of purported cobalt(lI) complexes, [Co(S2CNR2)2], derived from a range of amines including succi-nimide and phthalimide (49), p-naphthylamine (1125), and chloroanilines (1423). Others have claimed the preparation of those containing benzyl (506) and benzylpiperazine (1126), substituted piperidines (1116,1424,1425), and 1,3,4-thiaxolyl dithiocarbamate (1426). In none of this work was oxygen rigorously excluded. 

Ma et al. developed a copper-catalyzed cascade condensation/S-arylation/hetero-cyclization for the three-component synthesis of 2-iV-substituted benzothiazoles 113 from amines, carbon disulfide, and 2-haloanilines (Scheme 5.75) [78]. The first step in this process is the reaction between amine and carbon disulfide in the presence of bases to form dithiocarbamate salt A. Then, the in situ-generated A undergoes... 

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