Rhodium-Catalyzed Selective C( <i>sp</i> <sup>2</sup> )–H Activation/Annulation of <i>tert</i> -Butyl Benzoyloxycarbamates with 1,3-Diynes: A One Step Access to Alkynylated Isocoumarins and Bis-Isocoumarins
Bedadyuti Vedvyas Pati, Shyam Kumar Banjare, Gopal Krushna Das Adhikari, Tanmayee Nanda, Ponneri C. Ravikumar
Abstract
We report here a Rh(III) catalyzed regio- and stereoselective synthesis of alkynylated and bis-isocoumarin from 1,3-dialkyne. Exclusive one-pot formation of 3,3-bis-isocoumarin isomers has been achieved by eliminating several other possibilities. This is the first example of transition metal catalyzed synthesis of alkynylated and bis-isocoumarin scaffolds. The protocol is compatible with a wide range of functional groups affording good to excellent yields. Several mechanistic investigations, including deuterium labeling experiments and kinetic isotope effect studies, have been carried out.
Topics & Concepts
IsocoumarinsIsocoumarinChemistryAnnulationCatalysisRhodiumStereoselectivityDeuteriumCombinatorial chemistryMedicinal chemistryOrganic chemistryQuantum mechanicsPhysicsCatalytic C–H Functionalization MethodsSynthesis and Catalytic ReactionsCatalytic Alkyne Reactions