204376-35-2Relevant academic research and scientific papers
Convergent Synthesis of 2-Oxazolone-4-carboxylates Esters by Reaction of Aldehydes with Ambivalent N-Cbz-α-Tosylglycinate Ester
Abe, Masahiro,De Paolis, Micha?l,Picard, Baptiste
, (2020)
N-Cbz-α-tosylglycinate ester was combined with aldehydes in a redox-neutral sequence leading to 2-oxazolone-4-carboxylates with high functional group tolerance. While the scope of the method was delineated to primary and secondary aliphatic aldehydes as well as aromatics, no racemization occurred with chiral aldehydes such as Garner's. Hitherto unknown, this process relies on the ambivalent role of N-Cbz-α-tosylglycinate ester acting as a pronucleophile.
Synthesis of 2-oxazolone-4-carboxylates from 3-nosyloxy- and 3-bromo-2-ketoesters
Okonya, John F.,Hoffman, Robert V.,Johnson, M. Catherine
, p. 1102 - 1108 (2007/10/03)
New methods for the synthesis of 2-oxazolone-4-carboxylates from 3-nosyloxy- and 3-bromo-2-ketoesters are described. Condensation of 3-nosyloxy-2-ketoesters with methyl carbamate in refluxing toluene in the presence of p-TSA provided 2-oxazolone-4-carboxylates in good yields (41-80%). Alternatively, bromination of α-ketoesters with CuBr2 provided 3-bromo-2-ketoesters which condensed with methyl carbamate in the presence of p-TSA and AgOTfunder similar conditions to provide 2-oxazolone-4-carboxylates in comparable yields (30-79%). The 2-oxazolone-4-carboxylates bear functionality that can be elaborated to a variety of potentially useful compounds. For example, some of these heterocycles were readily N-acylated, reduced to alcohols, or saponified and coupled with amino acids.
Synthesis of 4-carboethoxy-4-oxazolin-2-ones from 3-nosyloxy-2-ketoesters
Hoffman, Robert V.,Johnson, M. Catherine,Okonya, John F.
, p. 1283 - 1286 (2007/10/03)
3-Nosyloxy-2-ketoesters, available from 2-ketoesters, react efficiently with methyl carbamate and tosic acid in refluxing toluene to provide 4-carboalkoxy-4-oxazolin-2-ones in good yields (41-84%).
