Dithiocarboxylic acid ester

Iodotriethyl(nthotrithiobenzoate, a readily accessible compound, on reaction with methanol loses ethanethiol to give the methylorthobenzoate (421 equation 198). Dialkoxydibutylstannanes convert dithiocarboxylic acid esters to oithoesters (422 equation 199). From orthoesters and chloral the orthoesters (423 equation 200) can be synthesized. "... 

In general, thiocarbonyl halides (59) function as thioacylation reagents with a variety of nucleophiles to yield the appropriate thio derivatives (60) (Scheme 31). For example, (59) on condensation with thiols, amines, potassium cyanide or potassium thiocyanide yields the corresponding thio compounds (60). Thiolocarboxylic acids (50) characteristically acylate alcohols and amines with desulfuration (Scheme 32). Dithiocarboxylic acid esters (54b) react with organolithium or Grignard reagents to give the dithioketals (61) after treatment with an alkyl halide (Scheme 33). 

Historically, the first chalcogenocarboxylic acid discovered was thiocarboxylic acid - thioacetic acid - reported by Kekule in 1854 [1]. Since then, chalcogenocarboxylic acids, and particularly numerous thio- and dithiocarboxylic acid esters, have been synthesized and summarized in several review articles [2-9]. In contrast, until very recently, little has been known about the chemistry of the congeners containing heavier chalcogen atoms, such as selenium and tellurium, probably due to their instability and the handling difficulties associated with them. In this chapter, the chemistry of chalcogenocarboxylic acids, their syntheses, structures, spectral features and reactions are reviewed. 

Sodium hydroxide Dithiocarboxylic acid esters by transesterification... 

Sodium hydrogen sulfide Thiocarboxylic acid chlorides from dithiocarboxylic acid esters via dithiocarboxylic acids... 

Monotbio-j -diketones. Acetophenone added slowly with stirring to a suspension of NaNHg in ether, after 15 min. an ethereal soln. of 0-methyl thiobenzoate added, stirred 3 hrs., and allowed to stand overnight monothiodibenzoyl-methane. Y 68%. E. Uhlemann and H. Muller, Ang. Gh. 77, 172 (1965) with Li, also from dithiocarboxylic acid esters, and f. method, s. E. Uhlemann and H. Muller, J. pr. 30, 163 (1965). 

Michael addition with dithiocarboxylic acid esters C = C CHC(R)... 

Amide mercaptals Di(alkylthio)-N,N-dimethyl-methylamines 20 Dithiocarbamic acids and esters Dithiocarbamidium salts Dithiocarboxylic acid ester S-imides... 

S-Alkylation with diazo compounds Dithiocarboxylic acid esters s. 19, 683 SH -> SR... 

Dithiocarboxylic acid esters from 1,1,1-trichlorides CCI3 CSSR... 

Thiocarboxylic acid esters s. Dithiocarboxylic acid esters, Thiolic —, Thionocarboxylic — Thiochromenes... 

In contrast to esters, elimination of the alkyl radical from the thiol site is the major fragmentation process. Ethylene sulfide is eliminated from thioesters with longer alkyl chains. Aromatic dithiocarboxylic acid esters usually fragment in two steps to the aryl cation. 

Sodium hydroxide Carboxylic acid thiohydrazides from dithiocarboxylic acid esters... 

Dithiocarboxylic acid esters from dithiocarboxylic acids and ethylene derivs. 

---