Thioacid halides

A high degree of stereospecificity with inversion has been reported for several other displacements of thioacid halides, including the reactions between (Pr 0)MeP(S)Cl and NaOMe, and between (R2N)PhP(S)Cl (97)(from ethyl prolinate and PhP(S)Cl2) and MeOH-Et3N " or NaOAr . 

A list of more common silver complexing agents includes thiosulfates, thiocyanates, sulfites, cyanides, ammonia and other amines, thiols, thiourea, thioacids, thioethers and alkali halides. Most are not practical as fixing agents because they fail to satisfy all the above criteria. Many find use as silver halide stabilizers (Section 59.2.1.8). These include thiocyanate, thiourea and other thioorganic compounds. These and other complexing agents such as cyclic imides, phosphines and arsines find use in silver halide diffusion transfer processes (Section 59.2.1.6). 

Perfluoroalkylmercury compounds have been prepared by reaction of perfluoroalkyl halides with cadmium amalgam or by reaction of fluoroalkenes with mercury(II) fluoride. Due to the high thermal stability of perfluoroalkylmercury compounds, they can be sublimed from concentrated sulfuric acid without decomposition and are of limited synthetic utility. These reagents have found use as difluorocarbene sources and do react with elemental sulfur at elevated temperatures to afford thioacid fluorides, di- and polysulfides, and thioketones. ... 

The alkyl halides (halogenoalkanes), thiols and amines are at the same oxidation level as the alcohols, while acyl halides, thioacids and amides are similarly related to the carboxylic acids. Like oxygen, sulfur can be inserted into a chain to generate the equivalent of an ether such as the thioether... 

Common types of radicals that add to n bonds are those that can be generated from alkyl halides, mercaptans, thiophenols, thioacids, aldehydes, and ketones. Like the corresponding electrophilic additions to double bonds, many radical additions are either regiospecific or highly regioselective. 

The n.m.r. spectrum of 2-chloro-l,3,2-dithia-arsenan (142) has been analysed and shown to be consistent with the predominance of one of the possible chair conformers. (see also ref. 842). The As-S bonds in arsenic-(m) thioacids, e.g. PhAs(SBu )2 and PhAsfSEOg, are broken by halogens and a number of non-metal halides to give PhAsXg- ... 

Sulfur Transfer Reagent Alkyl sulfides can be formed from the corresponding alkyl halides using TMS2S. Thioaldehydes, thioketones (eq 3), thioamides, thioacid anhydrides, thioacyl-silanes, divinyl sulfides (eq 4), and thiranes (eq 5) are also produced from TMS2S and their respective carbonyl or alkenic compounds, in combination with the reagents shown. 

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