Mechanism of the inverse-electron demand Diels–Alder reaction of 2-aminopyrroles with 1,3,5-triazines: detection of an intermediate and effect of added base and acid
摘要:
In base, a 2-aminopyrrole reacted with a 1,3,5-triazine to give a zwitterion (Meisenheimer complex). Acid promoted its conversion to the pyrrolo[2,3-d]pyrimidine. A cascade mechanism with reversible steps is proposed to explain why both a base and an acid are needed for the cycloaddition to occur. (c) 2007 Elsevier Ltd. All rights reserved.
The first example of tautomerism in 2-aminopyrroles: effect of structure and solvent
摘要:
Amino/imino tautomerism is observed in secondary 2-aminopyrroles when an electron-withdrawing group is on the amino group. The amino tautomer was favored in solvents that were hydrogen bond acceptors. (C) 2008 Elsevier Ltd. All rights reserved.