Oxidation of 5‐hydroxymethylfurfural and derivatives to furanaldehydes with 2,2,6,6‐tetramethylpiperidine oxide radical ‐ co‐oxidant pairs

Abstract

The oxidation of 5‐hydroxymethylfurfural (1) or 5‐hydroxymethylfurfurylideneacetophenone (4) with various 4‐substituted 2,2,6,6‐tetramethylpiperidine radicals (TEMPO) 3a‐d and supporting co‐oxidants gave corresponding aldehydes 2 or 5 in fair yields.

Catalytic Transformations of Biomass-Derived Materials into Value-Added Chemicals

“…Selective oxidation of the hydroxyl group of HMF, therefore, strongly required to form DFF. DFF synthesis had been examined using classical oxidants, including BaMnO 4 , pyridinium chlorochromate, NaOCl, and 2,2,6,6-tetramethylpiperydine-1-oxide (TEMPO), and also demonstrated by homogeneous metal bromide (Co/Mn/ Br) catalysts via autoxidation [191][192][193][194]. Furthermore, vanadium-based catalysts including V 2 O 5 [195], VOPO 4 Á 2H 2 O [196], and a V-containing polymeric catalyst [197] have been used previously.…”

Synthesis, Chemistry and Applications of 5‐Hydroxymethyl‐furfural and Its Derivatives

“…Cottier et al 104 reported the oxidation of HMF with various 4-substituted 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO) free radicals and supporting co-oxidants. They tested a variety of co-oxidants such as calcium hypochlorite, sodium hypochlorite-potassium bromide, copper (I) chloride-oxygen pair, p-toluenesulfonic acid, iodine in alkaline conditions or the electrochemically generated Br radical.…”

Ruthenium complex immobilized on poly(4-vinylpyridine)-functionalized carbon-nanotube for selective aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

“…[13][14][15] Nevertheless, the requirement of stoichiometric oxidants and the release of hazardous wastes are unavoidable for these methods. Therefore, selective oxidation of HMF to DFF with environment friendly molecular oxygen as oxidant satisfied the requirement of green chemistry.…”