124292-87-1Relevant articles and documents
Preparative route to 2-ethoxycarbonylimidazole-4-phosphonate and diethyl imidazole-2,4-dicarboxylate
Vuilhorgne, Marc,Malpart, Joel,Mutti, Stephane,Mignani, Serge
, p. 159 - 162 (2003)
Practical synthesis of 2-ethoxycarbonylimidazole-4-phosphonate (1a) and diethyl imidazole-2,4-dicarboxylate (1b) are described.
Synthetic method of thiazolecarboxylic chemical intermediate end intermediate
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Paragraph 0009, (2018/11/22)
The invention relates to a synthetic method of a thiazolecarboxylic chemical intermediate end intermediate, comprising: (a) mixing ethyl cyanoformate, isopropyl ether and isopropyl alcohol, and cooling under the protection of an inert gas to -20 DEG C to -5 DEG C; (b) mixing water, sodium bicarbonate, ice and methyl tertiary butyl ether, adding the intermediate, and keeping the temperature less than 0 DEG C and pH of weak basicity so as to free the intermediate; (c) adding compound 2 into ethyl alcohol, cooling by means of ice bath under the protection of an inert gas, and adding ammonium chloride to carry out reacting; (d) dissolving compound 3 in dichloromethane, and adding perchloromethylmercaptan under -10 DEG C to -5 DEG C; (e) dissolving compound 4 in ethyl alcohol, and dropwise adding sodium ethoxide-ethanol solution under ice-water bath and inert gas protection to carry out reacting. Therefore, chemical synthesis according to a new route can be provided for 5-ethoxy-1,2,4-thiadiazole-3-carboxylic acid end intermediate.
Synthesis of 4-Alkoxy-1,3-oxazol-5(2H)-ones, Precursors of 1-Alkoxy-Substituted Nitrile Ylides
Bozhkova, Nina,Heimgartner, Heinz
, p. 825 - 837 (2007/10/02)
4-Alkoxy-1,3-oxazol-5(2H)-ones of type 4 and 7 were synthesized by two different methods: oxidation of the 4-(phenylthio)-1,3-oxazol-5(2H)-one 2a with m-chloroperbenzoic acid in the presence of an alcohol gave the corresponding 4-alkoxy derivatives 4, presumably via nucleophilic substitution of an intermediate sulfoxide (Scheme 2).The second approach is the BF3-catalyzed condensation of imino-acetates of type 6 and ketones (Scheme 3).The yields of this more straightforward method were modest due to the competitive formation of 1,3,5-triazine tricarboxylate 8.At 155 deg C, 1,3-oxazol-5(2H)-one 7b underwent decarboxylation leading to an alkoxy-substituted nitrile ylide which was trapped in a 1,3-dipolar cycloaddition by trifluoro-acetophenone to give the dihydro-oxazoles cis- and trans-9 (Scheme 4).In the absence of a dipolarophile, 1,5-dipolar cyclization of the intermediate nitrile ylide yielded isoindole derivatives 10 (Schemes 4 and 5).