A Combination of Copper(I)‐Catalyzed Azide–Alkyne Cycloaddition Chemistry and Eliminative Azide–Olefinic Cycloaddition Reactions of Vinyl Sulfones: Synthesis of Vanillin Linked Homo and Hetero 1,2,3‐Triazolylated Divinyl‐1,2,3‐Bistriazoles and Their
Subhankar Santra, Rashmita Pan, Tanmaya PathakVanillin, a trifunctionalized phenolic compound manufactured on an industrial scale from biomass, is easily convertible to three different bifunctionalized forms. All these three chemicals, namely vanillic acid, vanillyl alcohol, and methoxyhydroquinone, along with vanillin, were used as starting materials for the synthesis of azide–alkyne, alkyne–alkyne, and vinyl sulfone‐alkyne orthogonally functionalized vanillin derivatives, which were used for the synthesis of bis‐( C/N )‐(1,4/1,5 or 1,5/1,4)‐disubstituted triazolylated moieties from the corresponding difunctionalized vanillin. Since vinyl‐1,2,3‐triazole monomeric units and related polymers combine the features of monomers made of styrenic, acrylate, or α‐olefin‐based units, the vanillin‐linked bis‐disubstituted triazoles were converted to bis‐( C/N )‐vinyl‐(1,4/1,5 or 1,5/1,4)‐disubstituted triazolylated moieties. C4 or/and N1 of 1,4‐disubstituted 1,2,3‐triazoles were prepared using a copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) strategy and C5 or/and N1 of 1,5‐disubstituted 1,2,3‐triazoles were obtained from alkyne equivalent vinyl sulfones via “Eliminative Azide–Olefinic Cycloaddition (EAOC)”. A unique selective thiophosphorylation method was identified, which specifically reacted with 4‐vinyl‐1,4‐disubstituted 1,2,3‐triazoles in vanillin linked homo and hetero 1,2,3‐triazolylated divinyl‐1,2,3‐bistriazoles to afford vanillin containing 1,2,3‐triazolylated organothiophosphates.