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Synthesis of unnatural α-amino esters using ethyl nitroacetate and condensation or cycloaddition reactions.

ABSTRACT: We report here on the use of ethyl nitroacetate as a glycine template to produce α-amino esters. This started with a study of its condensation with various arylacetals to give ethyl 3-aryl-2-nitroacrylates followed by a reduction (NaBH₄ and then zinc/HCl) into α-amino esters. The scope of this method was explored as well as an alternative with arylacylals instead. We also focused on various [2 + 3] cycloadditions, one leading to a spiroacetal, which led to the undesired ethyl 5-(benzamidomethyl)isoxazole-3-carboxylate. The addition of ethyl nitroacetate on a 5-methylene-4,5-dihydrooxazole using cerium(IV) ammonium nitrate was also explored and the synthesis of other oxazole-bearing α-amino esters was achieved using gold(I) chemistry.

SUBMITTER: Gagnot G

PROVIDER: S-EPMC6244114 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Synthesis of unnatural α-amino esters using ethyl nitroacetate and condensation or cycloaddition reactions.

Gagnot Glwadys G Hervin Vincent V Coutant Eloi P EP Desmons Sarah S Baatallah Racha R Monnot Victor V Janin Yves L YL

Beilstein journal of organic chemistry 20181115

We report here on the use of ethyl nitroacetate as a glycine template to produce α-amino esters. This started with a study of its condensation with various arylacetals to give ethyl 3-aryl-2-nitroacrylates followed by a reduction (NaBH<sub>4</sub> and then zinc/HCl) into α-amino esters. The scope of this method was explored as well as an alternative with arylacylals instead. We also focused on various [2 + 3] cycloadditions, one leading to a spiroacetal, which led to the undesired ethyl 5-(benza ...[more]

PMID: 30498535

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