Access to functionalized thienopyridines via a reagent-capsule-assisted coupling, thiolation and cyclization cascade sequence†
Abstract
Thienopyridines and related heterocycles were prepared in a straightforward manner in moderate to good yields and under mild conditions by palladium-catalysed cross-coupling of ortho-fluorinated iodopyridines and terminal alkynes, followed by a reagent-capsule-assisted thiolation cyclization process. By applying paraffin wax capsules to prevent catalyst poisoning and undesired side reactions, the separation and purification processes were reduced.