143359-71-1Relevant articles and documents
Cycloaddition of Carbodiimides with a Heteroaromatic Substituent to Allenic Acids
Trifonov, Latchezar S.,Christova, Nadja I.,Dimitrov, Valentin S.,Orahovats, Alexander S.
, p. 1262 - 1266 (1992)
Cycloaddition of the allenic acid 3 with the N-cyclohexyl-N'-heteroaromatic carbodiimides 2a and 2b gave the isomeric pyridopyrimidones 4 and 5 and thiazolopyrimidones 6 and 7, respectively, instead of the expected Diels-Alder adducts analogues to 1.The compounds of the latter type, i.e. 8 and 9, were formed from 3 and carbodiimides 2c and 2d, respectively, containing an N'-(pyrazin-2-yl) or N'-(pyrimidin-2-yl)substituent.