3H-Pyrroles from ketoximes and acetylene: synthesis, stability and quantum-chemical insight

作者：Shabalin Dmitrii A; Dvorko Marina Yu; Schmidt Elena Yu; Ushakov Igor' A; Protsuk Nadezhda I; Kobychev Vladimir B; Soshnikov Dmitrii Yu; Trofimov Alexander B; Vitkovskaya Nadezhda M; Mikhaleva Al'bina I; Trofimov Boris A^*

来源：Tetrahedron, 2015, 71(21): 3273-3281.

DOI：10.1016/j.tet.2015.03.111

• 3H-pyrroles
• Ketoximes
• Acetylene
• Superbases
• Hydroxypyrrolines
• Vinyloxypyrrolines

Rare nonaromatic 3H-pyrroles have been synthesized from ketoximes having only one C-H bond adjacent to the oxime function and acetylene under pressure (10-13 atm) at 70 degrees C in two-phase superbase media of KOH/DMSO/n-hexane type, the yields ranging 8-36%. The effect of substituents, superbase nature and reaction conditions on yields of the target 3H-pyrroles has been analyzed. Hydroxypyrroline/3H-pyrroles interconversion as well as relative stability of model 3H-pyrroles have been assessed quantum chemically (MP2/6-31++GB3LYP/6-31G**).