Highly efficient fixation of carbon dioxide into 2-oxazolidinones under mild conditions by using a reusable ionic liquid/CuI catalyst system

Abstract

A green approach was proposed for fixing CO2 with high efficiency and minimal energy consumption to produce 2-oxazolidinones through a one-pot reaction under mild conditions.

Asymmetric Multicomponent Propargylations via Carbon Dioxide Shuttling and Fixation

“…Inspired by the success of CO 2 shuttling in alkynylallylic and propargylic substitution reactions, we proposed that the corresponding cyclization under a CO 2 atmosphere should also be feasible (Scheme ). Indeed, by simply changing the original base DABCO with Et 2 MeN and reducing the amount of propargylic substrate 6 to 2.0 equiv, a Cu-catalyzed three-component propargylic substitution reaction was realized smoothly, providing a feasible route to the undeveloped asymmetric multicomponent propargylation in this area.…”

A Mechanistic Insight on CuI‐Catalyzed Synthesis of Oxazolidinones through a Four‐Component Reaction

“…The field of metal-catalyzed four-component coupling reactions towards oxazolidinone synthesis is rapidly evolving, [5] but most of the catalytic systems are based on Cu(I) [6] (few contributions involve Cu(II) catalytic precursors [7] ) or combinations thereof with engineered solvents such as ionic liquids to enhance the recyclability of the resulting catalytic systems. [8] From a mechanistic point of view, the seminal work reported by Li and coworkers proposed a mechanism for the A 3 -coupling carboxylative cyclization through the formation of the corresponding propargylamine intermediate and also pointing to a synergistic effect between the amine and CO 2 . [9] Later on, Hu and coworkers studied this four-component reaction using the preformed carbamate (coming from the reaction between the primary amine and CO 2 ) as reactant, proving that these reaction conditions permitted the synthesis of oxazolidinones using a lower catalyst loading (5 mol% of CuI); [10] these authors also studied the immobilization of Cu(II) salts on nano-Fe 3 O 4 for recycling purposes.…”