Palladium-Catalyzed Regio- and Stereoselective Hydrosulfonation of Propiolate Esters

Abstract

An efficient palladium-catalyzed addition reaction of alkyl- and arylsulfonic acids to propiolate esters to yield alkenyl sulfonates is demonstrated. The formation of alkenyl sulfonates is highly regio- and stereoselective with favorable yields of up to 95%, and two of the alkenyl sulfonates are utilized for a Sonogashira cross-coupling reaction to produce (Z)-1,3-enynoates.

Synthesis of Concave and Vaulted 2H-Pyran-Fused BINOLs and Corresponding [5] and [7]-Oxa-helicenoids: Regioselective Cascade-Concerted Route and DFT Studies

“…It is pertinent to note that crowded molecules usually are not accessible easily, and kinetically controlled pathways have to be invoked in most cases. Chromenes can be prepared via several routes, especially the metal-catalyzed C–H activation reactions involving the use of transition metals − such as indium, gold, platinum, palladium, rhodium, copper, and ruthenium . The metal-based reagents invariably are noxious and expensive.…”