Ammonium dithiocarbamate, condensation

In 1891, Miolati (75) confirmed the cyclic formula of Liebermann and Lange by preparing the compound by three new pathways (1) reaction of CS2 on thiohydantoin, (2) condensation of ammonium dithiocarbamate with chloroacetic ester, (3) reaction of HjS on thiocyanoacetic acid. 

During a relatively long period, the condensation of rhodanines with aldehydes was developed, especially by Andreasch s group (78-87). Finally, Holmberg (88, 89) described the best method to obtain rhodanines the condensation of ammonium dithiocarbamate with a sodium or potassium salt of an a-chloro acid. 

In 1892, Marchesini (94) described the synthesis of 4-phenyl-2-mercaptothiazole (62) by condensing bromoacetophenone with ammonium dithiocarbamate. 

The results initially obtained were due to the formation in both aqueous and alcoholic solution of resinous by-products. This formation results from the decomposition of the ammonium dithiocarbamate, or from the self-condensation of chloroacetaldehyde or the formation of intermediate products. 

Other sulfur compounds such as thiourea, ammonium dithiocarbamate, or hydrogen sulfide also lead to 2-mercaptothiazoles. Thus thiourea has been used in the syntheses of 4,5-dimethyl (369) and 4-aryl-2-mercapto-thiazoles (Table 11-30) (519). The reactions were carried out by condensing the ia -thiocyanatoketones with thiourea in alcohol and water acidified with hydrochloric acid. By this procedure, 4-aryl-2-mercaptothiazoles were obtained in yields of 40 to 80% with bis-(4-aryl-2-thiazolyl) sulfides as by-products (519). These latter products (194) have also been observed as a result of the action of thiourea on 2-chloro-4-arylthiazole under the same experimental conditions. They can be separated from 2-mercaptothiazoles because of their different degrees of solubility in sodium hydroxide solution at 5%. In this medium bis-(4-phenyl-2-thiazolyl)sulfide is... 

Mercaptoketones, condensation, with nitriles (or a-meicapto acids), 158 2-Mercapto-4-methyl-5-carbethoxythiazole, from ammonium dithiocarbamate and a-chloroacetoacetate, 264 2-Mercapto-4-methylthiazole, from chlor-aoetone yield of, 264... 

Benzo[2,3-d S,6-d bisthiazoles [C NS-CsNS-Cf,]. Condensation of chloranil with ammonium dithiocarbamates gives good yields of the derivatives (158) of the title compounds. ... 

A large-scale synthesis of the unsubstituted thiazole has been described starting from chloro-acetaldehyde and methyl dithiocarbamate <85S948>. Condensation of the two reagents affords 2-methylthiothiazole (272) which upon treatment with lithium in liquid ammonia and protonation with ammonium chloride yields thiazole (Scheme 69). 

Activated azodicarbonamide (WTR) Ammonium diethyl dithiocarbamate (WTR) see also ADC Condensation product from acetone and diphenylamine (WTR)... 

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