Ethyl N Tricarboxylate

Submitted by C. F. H. Allen and At an Beil Checked by Nathan L. Drake and Carl Blumenstein. 

Since water is usually present, it is advisable to distil the urethan before use, discarding the first 10%. 

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Ethyl N-tricarboxylate has been prepared from urethan by reaction with sodium and chlorocarbonic ester1 as well as from the potassium salt of ethyl imidodicarboxylate.2... 

Kthyl hydrazinecarboxylate has been prepared from hydra-zinc hydrate and ethyl N-tricarboxylate in good yield.5 The method described here is comparable in efficiency but has the added advantage that both starting materials are commercially available. 

In the presence of sodium, further acylation of ethyl carbamate by chloroformic ester gives ethyl N-tricarboxylate, N(C0jCjHs)3, in 57% yield."... 

EtEVL (3-PHENVL- 8-HyDIlOXYPEOPIO-NATE, 21, SI Ethyl propionate, 21, 43 Ethyl propylcyanoacetate, 26, 33 1-Ethylpyrrolidine, 26, 19 Ethyl succinate, 26, 42 Ethyl thiourea, 21, 84 S-Ethylthiuronium bromide, 22, S9 Ethyl N-tricarboxylate, 24, 60 Ethyl 7-veratrylbutyrate, 26, 29 Ethynylcarbinols, 22,101 1-Ethynylcyclohexanoi-1, 20, 41 Extraction, continuous, 20, 99 23, 49 hot, 20, 30... 

Diaminobiuret has been prepared only from N-tricarboxylic ester and hydrazine hydrate.1 Ethyl hydrazinecarboxylate has been prepared by reduction of nitrourethan electrolytically2 or with zinc dust and acetic acid,3 and by the action of hydrazine hydrate on diethyl carbonate,4 6 ethyl chlorocarbonate,6 and N-tricarboxylic ester.1... 

The presence or absence of the dioxolane protecting group in dienes dictates whether they participate in normal or inverse-electron-demand Diels-Alder reactions.257 The intramolecular inverse-electron-demand Diels-Alder cycloaddition of 1,2,4-triazines tethered with imidazoles produce tetrahydro-l,5-naphthyridines following the loss of N2 and CH3CN.258 The inverse-electron-demand Diels-Alder reaction of 4,6-dinitrobenzofuroxan (137) with ethyl vinyl ether yields two diastereoisomeric dihydrooxazine /V-oxide adducts (138) and (139) together with a bis(dihydrooxazine A-oxide) product (140) in the presence of excess ethyl vinyl ether (Scheme 52).259 The inverse-electron-demand Diels-Alder reaction of 2,4,6-tris(ethoxycarbonyl)-l,3,5-triazine with 5-aminopyrazoles provides a one-step synthesis of pyrazolo[3,4-d]pyrimidines.260 The intermolecular inverse-electron-demand Diels-Alder reactions of trialkyl l,2,4-triazine-4,5,6-tricarboxylates with protected 2-aminoimidazole produced l//-imidazo[4,5-c]pyridincs and the rearranged 3 / /- py r i d 0 [ 3,2 - d] py r i m i d i n - 4 -... 

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