N-heterocyclic carbene (thiamine) promoted eco-friendly synthesis of quinoxalines under mild reaction conditions

Abstract

An efficient and convenient protocol of broad scope for the synthesis of quinoxaline by cyclization-oxidation of phenacyl bromide with equimolar amount of phenylenediamine at room temperature catalyzed by thiamine in the form of N-heterocyclic carbene (NHC). High efficiency, inexpensiveness, and non-toxicity are the interesting features of the catalyst, which make it eco-friendly and highly attractive.

Design and Synthesis of Some New Quinoxaline‐Based Heterocycles

“…Many quinoxaline derivatives have a wide application as dyes, electroluminescent materials, organic semiconductors, cavitands, chemically controllable switches, and DNA cleaving agents . Also, some quinoxalines were used in the agricultural field as pesticides and used as chemical controllable switches, corrosion inhibitor , and insecticides .…”

Organocatalytic clean synthesis of densely functionalized 4H-pyrans by bifunctional tetraethylammonium 2-(carbamoyl)benzoate using ball milling technique under mild conditions

“…Furthermore, organocatalysis, namely the use of small organic molecules to catalyze organic transformations, is a relatively new and popular field within the domain of organic synthesis. Once the field of organocatalysis had been publicly defined, it grew quickly (32)(33)(34)(35)(36)(37). Although the impact of transition-metal-based catalysts on chemical synthesis cannot be completely understated, some metal-based systems can be expensive, toxic, and sensitive to air or moisture (38)(39)(40).…”