Chlorothioformates

Chlorothioformic phenyl ester (103) reacts under mild conditions wnth 2-aminothiazole to give 104 (Scheme 71) (266). 

Depending on the ring substituent, trifluoromethoxyben2enes can be made by the sequential chlorination—fluorination of anisole(s) (351—354). A one-step process with commercial potential is the BF (or SbF2)-cataly2ed reaction of phenol with carbon tetrachloride/hydrogen fluoride (355). Aryl trifluoromethyl ethers, which may not be accessible by the above routes,may be made by fluorination of aryl fluoroformates or aryl chlorothioformates with sulfur tetrafluoride (348) or molybdenum hexafluoride (356). 

Aryl chlorothioformates are prepared, for example, by reaction of a mixture of and NaHSO, CCl SCl, KI, and concentrated H2SO4 in... 

A number ot aryl trifluoromethyl ethers are synthesized by fluormation of aryl chlorothioformates with molybdenum hexafluoride. The reagents are progressively heated from -25 to 130 C, and the products are distilled off. Molybdenum disulfide and carbon disulfide are the by-products [12] (equation 16)... 

C7H5CIO2 1885-14-9) see Alacepril Camazepam Itraconazole Paroxetine t>-phenyl chlorothioformate (C7H5CIOS 1005-56-7) see Cladribine 4-phenylcinnoline... 

Ethanol amine dinitrate Ethyl chlorothioformate Ethylene chlorohydrin... 

Aryl chlorothioformates, 23 628 Aryl complexes, zirconium, 26 655 Aryl ethers, uses for, 70 581 2-Arylglycine esters, 72 166 Aryl halide amination, 9 278 Aryl halides, reaction with carbon monoxide, 5 11 Arylhydrazines, 9 270 Arylmethane dyes, 9 503... 

The extended (two-term) Grunwald-Winstein equation has been applied to the solvolyses of ethyl chloroformate (117) and ethyl chlorothioformate (118). For each substrate, there is evidence for two competing reaction channels. " Solvolysis... 

A new free-radical carbonylation strategy, employing S -phenyl chlorothioformates and alkyl halides, has been developed. Reaction with (Eu3Sn)2 furnishes the corresponding S -phenyl esters in moderate yields (Scheme 30). 

Amino-l,2,3,4-thiatriazole (207) when acylated with 0-aryl chlorothioformate (208) transforms into an unstable 5-aryloxy-3-imino-l,2,4-dithiazole hydrochloride (209). Acylation of this compound produces 2,5-bis(aryloxy)-l,6,6aA -trithia-3,4-diazapentalene ([210), which may be obtained more conveniently by acylating (207) with two equivalents of (208) (Scheme 44) <89M( 120)997, 90JPR208>. 

Graubaum et al. studied the reaction of 5-aminothiatriazole (10) with chloroformates in the presence of base and isolated 1,2,4-thiadiazoles (104 R = OR) <89M997, 90JPR208). In the reaction between 5-aminothiatriazole and chlorothioformates in the presence of base the main products were trithiapentalenes (116) (Scheme 21). However, in the absence of base the intermediary 5-alkoxy-and 5-aryloxy-3-imino-A -1,2,4-dithiazoline (115) hydrochlorides are isolated. These reactions are analogous to those of (10) and acid chlorides (Section 4.19.6.1.2). 

This type of compound is prepared from alkoxythiocarbonylhydrazines and nitrous acid or from (7-alkyl or (7-aryl chlorothioformates and sodium azide (Scheme 39) (see <84CHEC-I(6)579 . 

Allyloxy- (146) and propargyloxythiatriazoles (154) are obtained in a similar way by treating the corresponding chlorothioformates with sodium azide (92AG865). However, substituted allyloxy (150) and propargyloxy thiatriazoles (158) were obtained from 5-chloro-l,2,3,4-thiatriazole (175) in the presence of sodium hydride and the corresponding alcohols (35-70% yield) <92AG865>. 

Molinate (27) (65USP3198786) is simply made from perhydroazepine and 5-ethyl chlorothioformate, while the recently introduced pyrazolate (28) (75GEP2513750) is synthesized from l,3-dimethylpyrazol-5-one, itself easily made from methylhydrazine and ethyl acetoacetate. Reaction of the pyrazolone with 2,4-dichlorobenzoyl chloride takes place on carbon at the 4-position, and then treatment with toluene-p-sulfonyl chloride gives pyrazolate. Difenzoquat (29) (75USP3922161) is readily available from 3,5-diphenylpyrazole by methylation. Ethofumesate (30) (69GEP1926139) is synthesized from p-benzoquinone (Scheme 8). 

Aminolysis of phenyl dithioacetates,8 pyridinolysis of O-ethyl dithiocarbonates,9 reaction of pyrrolidine with O-ethyl 5-aryl dithiocarbonates,10 aminolysis of chlorothionformates,11 pyridinolysis of alkyl aryl thioncarbonates,12 reaction of anionic nucleophiles with nitrophenyl benzoate and its sulfur analogues,36 hydrolysis of methyl benzoate and phenyl acetate containing SMe, SOMe and S02Me substituents,42 solvolysis of phenyl chlorothioformate,79 synthesis of new thiadiazoles,124 examination of a neighbouring sulfonium group in ester hydrolysis,136 hydrolysis of V-type nerve agents,250 and the reactions of peroxymonosulfate ion with phosphorus(V) esters have all been looked at previously in this review. 

Graubaum and co-workers described the reactions of chlorothioformates 102 with 5-aminothiatriazole 90. Depending on the reaction conditions different products are formed. In the presence of a base, the main product is the trithiadiazapentalene 101, but in the absence of a base the dithiazolinimine hydrochlorides 100 are obtained (Scheme 23) <1989M997, 1990JPR208>. Thus, the reactivity of chlorothioformates is intermediate between that of acid chlorides and imidoyl chlorides. 

Chlorothioformic phenyl ester, with 2-amino-thiazoles, 51... 

Similar reactions have been carried out with amidines (67NEP6610627). Thus tri-chloroacetamidine (309) reacts with chlorothioformate esters to produce thioacyl products (310) which are readily oxidized to 5-alkoxy-3-trichloromethyl-l,2,4-thiadiazoles (311). The yields in both steps are about 80% (Scheme 111). The bromine oxidation of N-thiocarbamyl derivatives (312) of cyclic amidines (2-aminopyridine, 2-aminothiazole, 2-aminopyrimidine) yields thiadiazolium salts (313) (71JPR1148). In the 2-aminopyridine series, products of type (230 Scheme 81) are obtained in 20-73% yield when R is an ethoxycar-bonyl group (750PP55). 

CHLORO-4-THIOCHROMANYL o,o-DIMETHYL DITHIOPHOSPHATE see CLH820 CHLOROTHIOFORMIC ACID ETHYL ESTER see CLJ750... 

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