Synthesis of oxazolidine-2,4-diones by a tandem phosphorus-mediated carboxylative condensation–cyclization reaction using atmospheric carbon dioxide

Abstract

The oxazolidine-2,4-dione motif is found frequently in biologically important compounds. A tandem phosphorus-mediated carboxylative condensation of primary amines and α-ketoesters/base-catalyzed cyclization reaction have been developed. These processes provide a novel and convenient access to various oxazolidine-2,4-diones in a one-pot fashion using atmospheric carbon dioxide and readily available substrates under very mild and transition-metal-free conditions.

Understanding the mechanism, thermodynamic and kinetic features of the Kukhtin–Ramirez reaction in carbamate synthesis from carbon dioxide

“…[10][11][12] However, Zhang and coworkers reported a mild, convenient and environmentally friendly method by using CO 2 for synthesis of oxazolidine-2,4-diones. 13 Oxazolidine-2,4-diones are important class of the chemical compounds that are widely used in medicine and pharmaceutical industry. 14 P(NMe 2 ) 3 was used by Zhang and coworkers as a valuable phosphorous reagent for oxazolidine-2,4-diones synthesis.…”

“…14 P(NMe 2 ) 3 was used by Zhang and coworkers as a valuable phosphorous reagent for oxazolidine-2,4-diones synthesis. 13 Among the numerous organophosphorus with different valence states, trivalent phosphorus derivatives are known 15 which undergo an addition reaction with 1,2-dicarbonyl compounds to give 1 : 1 adducts formulated as either dioxaphospholene (A) or oxyphosphonium enolate (B) (Fig. 1).…”

DBU-promoted carboxylative cyclization of o-hydroxy- and o-acetamidoacetophenone

“…DBU and MTBD were previously reported as suitable bases to promote the carboxylation of α-C–H bonds in aromatic ketones with carbon dioxide [17–20]. In extension of our continuous efforts in developing catalytic transformations of carbon dioxide into value-added fine chemicals [20,22–23], we report herein the DBU-promoted carboxylative cyclization of o -hydroxy- and o -acetamidoacetophenones with carbon dioxide to give 4-hydroxy-2 H -chromen-2-ones and 4-hydroxy-2(1 H )-quinolinones, respectively, in moderate to good yields under mild reaction conditions. An acyl migration from the nitrogen to carbon is observed in the reaction of o -acetamidoacetophenone.…”

Nucleophilic Migratory Cyclopropenation of Activated Alkynes: A Nonmetal Approach to Unbiased Cyclopropenes

“…The adducts of trivalent phosphorus agents with 1,2-dicarbonyl compounds, known as the Kukhtin–Ramirez adducts (KRAs), have been widely used as convenient nucleophilic carbenoids in organic synthesis, , especially for rapid access to the highly substituted cyclopropanes from electron-deficient alkenes . However, there is no report on the reaction of KRAs with activated alkynes.…”