Ethyl thioglycolate

Pharmaceuticals and Agrochemicals. Thioglycohc acid and its esters are useful as a raw material to obtain biologically active molecules. In cephalosporine syntheses, (4-pyridyl)thioacetic acid [10351 -19-8] (65) and trifluoromethane (ethyl) thioglycolate [75-92-9] (66) are used as intermediates. Methyl-3-ainino-2-thiophene carboxylate can be used as intermediate for herbicidal sulfonylureas (67) and various thiophenic stmctures (68). 

Ethyl thioglycolate and ethyl cyanoacetate are first reacted in the presence of sodium ethylate to give 4-oxo-thiazolidin-2-ylideneacetic acid ethyl ester. That is reacted with diethyl sulfate and then with piperidine to give piprozolin. 

Ethylthioacrolein diethylacetal Dithiazanine iodide Ethyl thioglycolate Piprozolin... 

Ethylthio)ethanol, el80 Ethyl thioglycolate, el96... 

Reaction of 348 with the ethyl thioglycolate anion affords ethyl thieno[2,3-,7]pyridazine-2-carboxylate 349 in excellent yield <1994S669> (Equation 126). 

Azaindolizines (67a) react with ethyl thioglycolate anion in DMF to form the thio derivatives (67b). Substitution could not be effected when the 2-ester group was missing (81JOC1026). 3-Dimethylamino-2-nitro-l-azaindolizine (68b) has been formed from the chloride (68a) by a similar route (65JOC4085). 

The Vilsmeier-Haack reaction of ketones forms chlorovinyl aldehydes, which can add thiols readily. The reaction with a-tetralone gave the chlorovinyl aldehyde (230), and reaction with ethyl thioglycolate in ethanolic ethoxide solution formed the dihydro derivative (231), easily dehydrogenated to naphtho[l,2-6]thiophene-2-carboxylate (73JCS(P1)2956). 

Treatment of the aldehyde (86 R = H) with ethyl thioglycolate and sodium ethoxide provides an elegant single-stage synthesis of the otherwise rather inaccessible ethyl 5-nitrobenzo[6]thiophene-2-... 

Ethyl pyruvate, el96 2-(Ethylthio)ethanol, el 53 Ethyl thioglycolate, el 64 Ethyltriethoxy silane, t261... 

Nucleofuges, other than the chlorine atom, can be involved in these reactions. For example, 1,2-bipyridinium chloride 25 reacts with ethyl thioglycolate with elimination of pyridine to form sulfide 26, whose isomerization to thienopyridine 27 occurs under conditions of the Thorpe reaction (1998T5775). 

Cycloaddition of bis(imidoyl chloride) 94 with the dianion of ethyl thioglycolate 93 allowed the synthesis of 2,3-diiminothietane 95 in 30% yield (Equation 30) <1999CC2439>. The thietane 95 was easily isolated by column chromatography. 

The reaction between lithiated ethyl thioglycolate and l,2-diimidoyl-l,2-dichloroethanes is complex and the products depend on the reaction conditions. When a large excess of the monoanion of ethyl thioglycolate is used, good yields of 2,3-diamino4-thioxo4//-thiopyran-6-carboxylates are obtained (Equation 177) <2006JOC2332>. 

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