Valorization of 2,5-furandicarboxylic acid. Diels–Alder reactions with benzyne

Abstract

Biomass-derived 2,5-furandicarboxylic acid was valorized by conversion to 1,4-naphthalenedicarboxylic acid via benzyne-cycloaddition and reductive aromatization in 66% overall yield (four steps).

Work‐hardening Photopolymer from Renewable Photoactive 3,3’‐(2,5‐Furandiyl)bisacrylic Acid

“…Monomer synthesis: Monomer 1 was described as early as 1914 and was recently used in reactions with benzyne for the production of potential terephthalate replacement. [22,23] However, to the best of our knowledge, no details on 1's photoactive properties have thus far been presented. Synthesis of 1 begins with the oxidation of HMF to 2,5-diformyfuran (DFF, Figure 1, 13 and 15 respectively).…”

“…Previous reports made use of the aldehyde manifold present in furfural or HMF for extending the conjugation of these compounds by incorporating an unsaturated moiety via Knoevenagel condensation. [17,23] DFF was thus considered to be an excellent candidate for the double Knoevenagel-Doebner condensation reaction and afforded the E-E intermediate 16 (Figure 1, 16) in 82 % isolated yield with 100 % stereoselectivity. Although pyridine was used as solvent in this Knoevenagel condensation, encouraging results have been reported using ionic liquids (up to 62 % yield) or solvent-free systems (99 % using malononitrile).…”

Leaving Groups in Metal‐Free Arylations: Make Your Choice!

“…Synthesis of 1,4-naphthalenedicarboxylic acid 21 via aryne intermediate. [101] Diels Alder reaction followed by reductive aromatization of 7-oxabenzonorbornadiene 20 and hydrolysis in 66 % overall yield. [101] 5.2 Aryl Diazonium Derivatives 1-Aryl-3,3-dialkyltriazenes are usually considered as aryldiazonium salts equivalents, smoothly obtained by treatment of the salts with a secondary amine.…”

“…[101] Diels Alder reaction followed by reductive aromatization of 7-oxabenzonorbornadiene 20 and hydrolysis in 66 % overall yield. [101] 5.2 Aryl Diazonium Derivatives 1-Aryl-3,3-dialkyltriazenes are usually considered as aryldiazonium salts equivalents, smoothly obtained by treatment of the salts with a secondary amine. [102] Such compounds undergoes thermal decomposition under Brønsted or Lewis acid conditions [103] and a sparse literature on their use as arylating agents is available.…”

Valorisation of Cashew Nut Shell Liquid Phenolics in the Synthesis of UV Absorbers

“…It has been estimated to provide about 25 % of global energy requirements . In recent times there has been significant interest in developing strategies for the use of non‐edible biomass as a sustainable alternative to petroleum and petroleum based products . This paradigm shift is necessitated by diminishing petroleum reserves, the rise of oil prices, the negative effects of petroleum on the environment and the advantages of using fast‐growing non‐edible biomass as a sustainable resource .…”