Lithium ethoxycarbonyl chloride

C-Acylation and -carboxylation also occur with pyrrole Grignard reagents (p. 106). Whilst lithium pyrrole and lithium 2,4-dimethylpyrrole react with ethoxycarbonyl chloride to give ethyl pyrrole-2- and 2,4-dimethylpyrrole-5-carboxylate, respectively the corresponding potassium salts give the N-substituted pyrroles (p. 81). 

The case of ethoxycarbonylation has also been mentioned (p. 66). Whilst potassium salts of pyrrole and alkyl pyrroles react with ethoxycarbonyl chloride to give l-ethoxycarbonylpyrroles257, 291-2 the lithium salts form... 

Via an amidoalkylation of bis(trimethylsilyl)ethyne (12) with methyl 2-chloro-N-ethoxycarbonylglycinate (57) under the influence of aluminum chloride the corresponding N-(ethoxycarbonyl)-a,a-TMS-ethynyl-glycinate (55) is isolated which is converted by means of lithium-di-isopropylamide (LDA) into a carbanion that reacts with alkylhalide to the substituted glycinate 59. Finally, after alkaline hydrolysis the unprotected a-acetylenic-a-aminoacid (60) (e. g. R = Benzyl a-ethynyl-a-phenyl-alanine is then obtained (Scheme 7). 

Methyl esters 333 that are activated toward decarboxylation by a C-2-ethoxycarbonyl group and tethered by an alkyl chain to an acrylate Michael-acceptor undergo chemoselective S] [2-dealkylation of the methyl ester, decarboxylation and cyclization upon exposure to lithium chloride in DMEU, affording tetrahydropyrans in excellent yield and diastereoselectivity (Equation 142) <1998JOC144>. 

In a related reaction, ethyl cyanoacetate is the source of the cyano(ethoxycarbonyl)methylene unit which is transferred to alkenes by a radical mechanism, e.g. synthesis of 3. This transformation is mediated by copper(II) chloride or acetate, accompanied by lithium chloride. Synthesis of diethyl cyclopropane-1,1-dicarboxylates from diethyl malonate and alkenes is much less efficient. ... 

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