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.
Method for synthesizing intermediate product thiazolecarboxylic acid chemical intermediate
-
Paragraph 0016-0018, (2018/12/02)
The invention relates to a method for synthesizing an intermediate product thiazolecarboxylic acid chemical intermediate, comprising the following steps: (a) mixing ethyl cyanoformate, isopropyl etherand isopropanol, and cooling to minus 20- minus 5 DEG C under the inert gas protection; (b) stirring and mixing water, sodium bicarbonate, ice and methyl tert-butyl ether, adding the intermediate, keeping the water temperature below 0 DEG C and keeping the pH to be weakly alkaline so as to free the intermediate; (c) adding the compound 2 into ethanol, cooling under the inert gas protection with an ice bath, and adding ammonium chloride for a reaction; (d) dissolving the compound 3 in dichloromethane and adding perchloromethyl mercaptan at minus 10- minus 5 DEG C. The method of the invention is conducive to industrial batch production of 5-ethoxy-1,2,4-thiadiazole-3-carboxylic acid.
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).