Palladium-Catalyzed Intramolecular Allylic Amidation via Decarboxylative Aromatization: Synthesis of N-Allyl-N-aryl Sulfonamides

Base-Mediated Coupling Reactions of Benzenesulfonyl Azides with Proline: Synthesis of Proline-Derived Benzenesulfonamides

Sulfonamides and lipids are widely found in natural products, bioactive substances, and pharmaceuticals. Here, we report N-sulfonylation and esterification of carboxylic acids in an environment-friendly one-pot tandem protocol involving 1,2-dichloroethane (DCE). Moreover, 1,8-diazabicyclo (5.4.0) undec-7-ene was necessary for this reaction as a strong base, which drives the reaction to completion. Although DCE is a very low activity reagent, it acts not only as a solvent but also as a reactant in the reaction. The β-chloroester contained in the reaction product can be easily dissociated to react with N, S, and O atoms, increasing the possibility for subsequent synthesis.

Palladium-Catalyzed Regiospecific Decarboxylative Allylation of (Cyclohexadienylidene)malononitriles: Access to α-Allyl-α-aryl Malononitriles

A palladium-catalyzed regiospecific decarboxylative ε-allylation of (cyclohexadienylidene)malononitriles is presented for the synthesis of functionalized α-allyl-α-aryl malononitriles. This reaction proceeds via a resonance-stabilized α-aryl malononitrile anion, resulting in a wide range of α-allyl-α-aryl malononitriles in high yields with excellent linear product selectivity. We have also shown that the resulting products can be transformed into valuable synthetic intermediates by decyanation and Mizoroki-Heck arylation. In addition, an enantioselective decarboxylative allylation reaction is also presented.