Nucleophilic substitution with dithiocarbamate

In analogy to the reaction of 3,5-dichlorothiatriazine with thiolates, the same reaction type proceeds with sodium dithiocarbamate (X = S) to yield 3-chloro-Ar,Ar-dialkyl-5-(thiocarb-amoylsulfanyl)-lA4,2,4,6-thiatriazin-l -amines 19a-c as stable crystalline compounds. Further nucleophilic substitution is not observed.45... 

The nucleophilic reactivity of dithiocarbamate anions has been the subject of a variety of papers, describing the reactions of alkali-metal dithiocarbamate salts with the common organic solvents methylene chloride, chloroform, and acetonitrile, with alkyl halides, a-halogeno-ketones and -aldehydes, chloroacetates, chloro-substituted j-triazines, phthaloyl chloride, oxalyl chloride, and with AW-dimethyl-5 S -dimethyldithiocarbamidium perchlorate. The nucleophilic addition reaction of dialkylammonium NN-dialkyldithiocarbamates with olefins, yielding alkyl dithiocarbamates, has also been described. ... 

Nucleophilic Substitutions. 7V,7V-Dimethyldithiocarbamoyl-acetonitrile (1) serves as an active methylene compound, because its carbanion is stabilized by sulfur and cyano groups. It can be alkylated stepwise in aqueous sodium hydroxide under phase transfer catalysis (eq 1). The anion undergoes nucleophilic aromatic substitution to give nitroarenes, with elimination of the dithiocarbamate group (eq 2). Nucleophilic addition of (1) to phenyl isothiocyanate also occurs readily. ... 

This reaction was first reported by Hantzsch and Weber in 1887. It is the formation of thiazole derivatives by means of condensation of a-haloketones (or aldehydes) and thioamides. Therefore, it is generally known as the Hantzsch thiazole synthesis. In addition, other names, including the Hantzsch synthesis, Hantzsch reaction, and Hantzsch thiazole reaction are also used from time to time. Besides thioamides, other thio-ketone derivatives such as thiourea, dithiocarbamates, and ketone thiosemicarbazone can also condense with a-halo ketones (or aldehydes) to form thiazoles. This reaction occurs because of the strong nucleophilicity of the sulfur atom in thioamides or thioureas, and normally gives excellent yields for simple thiazoles but low yields for some substituted thiazoles, as of dehalogenation. This reaction has been proven to be a multistep reaction, and the intermediates have been isolated at low temperatures, in which the dehydration of cyclic intermediates seems to be the slow step. It is found that a variety of reaction conditions might result in the racemized thiazoles that contain an enolizable proton at their chiral center, and it is the intermediate not the final product that is involved in the racemization. Therefore, some modifications have been made to reduce or even eliminate the epimeriza-tion upon thiazole formation. In addition, this reaction has been modified using a-tosyloxy ketones to replace a-haloketones. ... 

Rate constants for the substitution reactions of square-planar dithiophosphate and dithiocarbamate complexes of Ni , Pd, and Pt, with en and CN as nucleophiles, have been reported with methanol as the solvent the general mechanism... 

Dithiocarbamates are nucleophiles and undergo substitution reactions with simple organic halides to produce new organosuUur compounds (31). For example, addition of NaS2CNMe2 to 1,2-dichloroethane (160), and chloroform (31) affords the compounds (12 and 13), respectively, while the same concept can be used to prepare more elaborate organosulfur compounds such as (14 and 15) (106, 161). 

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