Thiocarbamoyl chlorides

Prepared from Clj and [Mc2NC(S)S ]2 or the corresponding thiocarbamoyl chloride. 

The naphthalene-catalyzed (3%) lithiation of carbamoyl or thiocarbamoyl chlorides 91 in the presence of carbonyl componnds or imines as electrophiles in THF at temperatnres ranging between —78 to 20 °C led to the expected fnnctionalized amides or thioamides 92 after hydrolysis (Scheme 39) . ... 

Replacement of the urethane carbonyl function by an aromatic ring leads to a benzo-thiazole that is described as an immune function modulator. In an analogous approach to that used above, anilinothiol (63-1) is condensed with the thiocarbamoyl chloride (63-2) again in the presence of a base. This leads directly to frentizole (63-3) [66]. 

In the next section the formation of acyl anion equivalents by nucleophilic addition to thiocarbonyl compounds is discussed. A direct and non-classical route to thiocarbonyl anions has been achieved [141]. Treatment of a thiocarbamoyl chloride by lithium powder, in the presence of both naphthalene and the carbonyl compound to which the intermediate will be added, led to a-hydroxy thioamides. 

An oc-functionalised carbenoid intermediate 26 can be made from 25,37>38 and acyllithiums 28 and 30 are available from the carbamoyl chloride 27 and thiocarbamoyl chloride 29.39 Lithiated sugars may also be made from chloropyranosides (see below).40... 

A more direct way for the preparation of carbamoyl and thiocarbamoyllithiums started from carbamoyl and thiocarbamoyl chlorides 119 and used lithium powder and a catalytic amount of naphthalene (3 mol%)113,114. The lithiation was performed at —78°C in the presence of carbonyl compounds and imines as electrophiles to yield products 120 (Scheme 32). Phenyl isocyanate and DMF afforded oxamides in modest yields (21 and 42%, respectively). 

The reaction of 4-fluoro-2,6-di-tert-butylphenol (290) with N,N-dimethyl-thiocarbamoyl chloride (291) in the presence of DBU in dimethylformamide... 

In contrast to thioacyl chlorides, thiophosgene, CSCh, is readily accessible and conveniently handled making it an important reagent in the synthesis of thiocarbamoyl chlorides (15 ClCSNRa), 0-alkyl thiourethanes (ROCSNR 2), and thioureas (R2NCSNR2) (c/. Volume 6, Chapter 2.8). ... 

On the other hand, thiocarbamoyl chlorides (15) may be used in thioamide synthesis, though via carbon-carbon bond formation in Friedel-Crafts-type reactions (c/. Volume 2, Chapter 3.1). The approach is limited to fairly electron-rich aromatics such as alkylbenzenes, anisole, and furan, but fails for benzene equation (7) gives some details. - Phenol does not require a Lewis acid catalyst in the reaction with H CSCl, but gives a mixture of 2-/4-hydroxythiobenzamides along with O-phenyl thiocarba-mate. ... 

Another application of thiocarbamoyl chlorides (15) and related activated thiocarbonic acid derivatives in thioamide synthesis is found in their reaction with carbanions of highly CH acidic compounds EWG2CH2 to give thioamides EWG2CHCSNR2. ... 

Other preparative routes to isothiocyanates involve reaction of amines with carbon disulfide and alkali and subsequent treatment of the dithiocarbamate (112) with phosgene or ethyl chloroformate. Alternatively, the dithiocarbamate may be reacted with mercury(II) chloride or lead tetranitrate (Scheme 61). Amines can also be reacted with thiophosgene or N,N-diethyl thiocarbamoyl chloride (113) (Scheme 61). 

OLEFINS f-Butyl hydroperoxide. Diethyl phosphorochloridate. Di-methylcopper lithium. N,N-Dimethyl-thiocarbamoyl chloride. Trimethyl phosphite. Triphenylphosphine. 

AP833>, and 3-acyl-3,4,5,6-tetrahydro-l,3-thiazine-2-thiones (59) are formed in the same way from the parent 3,4,5,6-tetrahydro-l,3-thiazine-2-thiones (60) (Equation (7)) <84AP74>. Both types of product are unstable and can be used as transacylating agents for amines and thiols. Thiocarbamoyl chlorides also react with 3,4,5,6-tetrahydro-l,3-thiazin-2-ones, but here both N- and (9-thio-carbamoylation can occur <86LA1140>. 

Thiocarbamoyl chloride itself is produced by addition of hydrogen chloride to thiocyanic acid in anhydrous ether 774... 

Dithiocarbamic esters can generally be obtained easily by alkylation or arylation of the corresponding dithiocarbamic salts 792-798 other methods are addition of thiols to isothiocyanic esters,792 treatment of chlorodithio-formic esters with amines,792 and reaction of thiocarbamoyl chlorides with thiolates.786... 

Carbamoyl and thiocarbamoyl chlorides also undergo exchange to give the corresponding lithium reagents. These are readily trapped by carbonyl compounds to afford 2-hydroxy carboxamides. ... 

Marcaccini s group also used ethyl isocyanoacetate as a precursor to iso-thiocarbamoyl chlorides, which were cychzed to 5-alkoxy-2-(arylthio)oxazoles (Scheme 1.98). Thus low-temperature addition of an arylsulfenyl chloride to ethyl isocyanoacetate generated an isothiocarbamoyl chloride 361 quantitatively. These can be isolated if desired, but crude 361 cyclized readily with (C2Hs)3N at —20°C to produce 5-aIkoxy-2-(arylthio)oxazoles 362, also in near quantitative yield. The authors noted that these were the first examples of oxazoles containing both alkoxy and arylthio substituents. 

The reaction of potassium cyanodithioimidocarbonate with dlmethyl-thiocarbamoyl chloride did not yield the expected product A, but instead furnished the titled sulfide (59). 

Secondary amides are oxidized, as their iV-trimethylsilyl derivatives, to the corresponding hydroxamic acids by a molybdenum oxide-HMPA complex. NN-disubstituted thiocarbamoyl chlorides or bromides are easily prepared by direct reaction of the corresponding thioformamides with elemental halogen. 

OCH3 - Obtained by stirring a mixture of 2,4-dihydroxy-phenyl 4-methoxybenzyl ketone (1 mol), dimethyl- thiocarbamoyl chloride... 

Aminosilanes have been used to prepare thiocarbamoyl chlorides RgNCSCl from thiophosgene, silylenols from 1,2-diketones, and monosilylated p-quinol derivatives from (Me3SiO)gPH and p-benzoquinone. Stabilized primary... 

The thioacylation of NH groups by dithiocarboxylic esters and their salts, as well as by thionocarboxylic esters, is dealt with in Section 5 of this chapter. Diphenylcyclopropenethione reacts with amines to give the cycloadducts (91), which are rearranged to the thioamides (92) when heated in benzene. Thioamides RNHC(S)CHXY are obtained from compounds with active methylene groups by reaction with A-aryldithiocarbamic acid esters, e.g. MeSC(S)NHPh, thiocarbamoyl chlorides, or C-sulphonylthioformamides,... 

Thioamides have been obtained by allowing aromatic hydrocarbons to react with thiocarbamoyl chloride in carbon disulphide in the presence of aluminium trichloride. When 1-alkynyl propargyl sulphides are dissolved in a solution of a dialkylamine in DMSO or methanol, the thioamides of penta°3,4 and penta-2,4-dienoic acids are formed, as shown in equation (4). ... 

Some papers dealing with the preparation and properties of metal complexes of thiocarbamoyl chlorides," dithiocarbamates, " and selenothiocarbamates" may be of interest to workers in that field. 

Mercapto-1,2,5-thiadiazoles are obtainable by a procedure based on the rearrangement of thiono- into thiol-carbamates. It comprises the thioacyla-tion of (226) with thiocarbamoyl chloride, then rearrangement of the resulting thionocarbamate (227) at 130 C into (228), followed by hydrolysis. The resulting labile thiol is stabilized as the potassium or mercury salt (229), or as the 4-methoxycarbonylmethyl derivative (230). The i.r. spectrum (in... 

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