Regio‐ and Stereoselective Ring‐Opening Reactions of Epoxides with Indoles and Pyrroles in 2,2,2‐Trifluoroethanol

Abstract

Aliphatic and aromatic epoxides react regio- and stereoselectively with indoles and pyrroles in 2,2,2-trifluoroethanol without the use of a catalyst or any other additive. While aromatic epoxides are selectively attacked at the benzylic position, aliphatic epoxides react at the less-substituted position. Chiral epoxides react with >99 % ee (ee=enantiomeric excess).

A facile and efficient synthesis of β-amino alcohols using 2,2,2-trifluoroethanol as a metal-free and reusable medium

“…We propose hydrogen bonding interaction and amine reactivity are the main factors that influence the regioselectivity of the process. This regioselectivity was observed previously in the literature [61]. When we carried out the reaction between cyclohexene oxide and aniline in TFE at room temperature, the result was similar to Bé gué 's study [52].…”

A facile and efficient synthesis of 2-amino-3-cyano-4H-chromenes and tetrahydrobenzo[b]pyrans using 2,2,2-trifluoroethanol as a metal-free and reusable medium

“…Therefore, the search continues for a better catalyst for the synthesis of pyrans in terms of operational simplicity, reusability, economic viability, and greater selectivity. The use of fluorinated solvent, as chemical reaction media in place of conventional volatile organic solvents, has grown dramatically in recent years [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50]. Fluorinated alcohols possess interesting physiochemical properties, which include lower boiling points and higher melting points than their non-fluorinated counterparts, high polarity, strong hydrogen bond donation properties and the ability to solvate water.…”

Fluorinated alcohols: A magic medium for the synthesis of heterocyclic compounds

“…M a n u s c r i p t 5 protection and deprotection of amine groups, [39,40], cyclopropanation of alkenes [41], and oxirane ring-opening without any catalyst [42,43].…”