Raja D, Philips A, Sundaramurthy D, Chandru Senadi G. Sustainable Synthesis of 2-Hydroxymethylbenzimidazoles using D-Fructose as a C
2 Synthon.
Chem Asian J 2021;
16:3754-3759. [PMID:
34549532 DOI:
10.1002/asia.202100972]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/17/2021] [Indexed: 12/11/2022]
Abstract
D-fructose, a biomass-derived carbohydrate has been identified as an environmentally benign C2 synthon in the preparation of synthetically useful 2-hydroxymethylbenzimidazole derivatives by coupling with 1,2-phenylenediamines. Proof of concept was established by synthesizing 23 examples using BF3 .OEt2 (20 mol%), TBHP (5.5 M, decane) (1.0 equiv.) in CH3 CN at 90 °C for 1 h. The pivotal features of this method include metal-free conditions, short time, good functional group tolerance, gram scale feasibility and the synthesis of benzimidazole fused 1,4-oxazine. Control studies with conventional C2 synthons did not produce the desired product, thus suggesting a new reaction pathway from D-fructose.
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