FIRST SYNTHETIC METHOD FOR THE PREPARATION OF 6-UNSUBSTITUTED-2,3-DIHYDRO-1,3-OXAZIN-4-ONES

摘要

The first synthetic pathway to synthesize 6-unsubstituted-2,3-dihydro-1,3-oxazin-4-ones is described. The alpha-formylation of the starting amide and the cyclization of the alpha-formylamide with a desired aldehyde under acidic conditions gave compounds 5a-h (R = nPr, iPr, cPr, cHex, Ph, CH(2)Ph, nHex, and R(1) = H, Me). This strategy was used with little modification for the preparation of new monocyclic organic nitrates such as 2a-c (2a (R = Ph, R(1) = H, and R(2) = H), 2b (R = Ph, R(1) = H, and R(2) = Me), and 2c (R = H, R(1) = Ph, and R(2) = H). [References: 7]