Butadiene sulfone as ‘volatile’, recyclable dipolar, aprotic solvent for conducting substitution and cycloaddition reactions

Abstract

Butadiene sulfone has been employed as a "volatile", recyclable dipolar, aprotic solvent in the reaction of benzyl halide with metal azides to form benzyl azide (1) and the subsequent reaction of benzyl azide with p-toluenesulfonyl cyanide (3) to produce 1-benzyl-5-(p-toluenesulfonyl)tetrazole (2). Comparisons are made with the solvent DMSO and an analogous sulfolene solvent-piperylene sulfone. In addition, recycling protocols for butadiene sulfone and piperylene sulfone are also presented.

A Glimpse into Green Chemistry Practices in the Pharmaceutical Industry

“…In product separation, isolation, and post‐production treatment, these solvents have proven better than conventional solvents. Examples of alternative solvents include ionic liquids, liquid polymers, supercritical carbon dioxide (scCO 2 ), switchable solvents, and very importantly, water . Benign solvents derived from renewable biological sources are given preference owing to their availability and sustainability .…”

Hydrophobic 2,7-Octadienyl Ether-Cellulose Nanofibrils Using Butadiene Sulfone as the Dual Reagent and Medium

“…Structurally, BDS is analogous to piperylene sulfone, which carries an extra C1 methyl group and has similar physical properties (dipole moment D = 5.32, dielectric constant ε = 42.6, and solvent polarity π* = 0.87) as DMSO ( D = 4.27, ε = 46.7, and π* = 1.00), a common solvent for diverse organic reactions. At above 90 °C, BDS undergoes reversible cheletropic degradation into gaseous 1,3-butadiene (BD) and sulfur dioxide (SO 2 ), which have been shown to revert back to liquid or solid BDS at up to 96% upon cooling in the presence of excess SO 2 and 1 wt % hydroquinone inhibitor in a sealed environment. , As a reagent, BDS has been shown to be a safer source of 1,3-BD for Diels–Alder reactions between conjugated diene and maleic anhydride or 1,4-dihydronaphthalene than the highly volatile ( T b = −4.4 °C) counterpart. In the presence of water, BDS could also supply sulfurous acid to simultaneously solubilize lignin and hydrolyze xylan in biorefining. , …”

“…At above 90 °C, BDS undergoes reversible cheletropic degradation into gaseous 1,3-butadiene (BD) and sulfur dioxide (SO 2 ), which have been shown to revert back to liquid or solid BDS at up to 96% upon cooling in the presence of excess SO 2 and 1 wt % hydroquinone inhibitor in a sealed environment. 25,26 As a reagent, BDS has been shown to be a safer source of 1,3-BD for Diels−Alder reactions between conjugated diene and maleic anhydride 27 or 1,4dihydronaphthalene 28 than the highly volatile (T b = −4.4 °C) counterpart. In the presence of water, BDS could also supply sulfurous acid to simultaneously solubilize lignin and hydrolyze xylan in biorefining.…”