Synthesis of Oxazolidin‐2‐ones from Unsaturated Amines with CO₂ by Using Homogeneous Catalysis

Abstract

Carbon dioxide (CO ), a well-known greenhouse gas, is also a nontoxic, readily accessible, and renewable one-carbon (C1) source. However, owing to its thermodynamic stability and kinetic inertness, the efficient utilization of CO is challenging. Much effort has been devoted to achieving efficient and selective organic transformations of CO . Recently, the synthesis of important oxazolidin-2-ones from unsaturated amines by using CO has attracted much attention and been heavily studied. This Focus Review presents recent advances in this area by using homogenous catalysis. The cyclization of amines that contain alkynes, alkenes, and allenes with CO is discussed, and possible reaction mechanisms and applications of these transformations are also described.

Recent Advances in the Chemical Fixation of Carbon Dioxide: A Green Route to Carbonylated Heterocycle Synthesis

“…The synthesis of oxazolidin-2-ones from unsaturated amines by using CO 2 has attracted much attention in the last years [152]. A study of the reaction mechanism with the ωB97XD functional theory was conducted by Yuan and co-workers under Ag(I) catalysis [153].…”

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C−N Bond Forming Reactions of Amines with CO2

“…Reactions of aziridines, [99][100][101] propargylic amines,a llylic amines and 1,2-aminoalcohols with CO 2 yield oxazolidinones and their derivatives (Scheme 12) [102][103][104][105][106][107] and six-membered oxazin-2-ons from allenic amines [108,109] or 2-ethynylaniline (Scheme 13). [110] 2-Ethynylanilines are isostructural with 2- Figure 14.…”

“…Thec yclization of propargylic amines,a llylic amines and allenic amines follows as imilar mechanism. [106] Internal cyclization of the carbamate anion with an unsaturated C À Cb ond yields the reaction products after protonation. Due to low polarity of unsaturated CÀCb onds,t he cyclization step is usually ratedetermining.D BU, [112] MTBD [113] and other guanidines, [114] tertiary amines, [115] NHCs, [116] K 2 CO 3 [108] and various ILs have been used to stabilize the carbamate before cyclization ( Figure 15).…”

“…Overall, base catalysts used in the synthesis of oxazolidinones and oxazin‐2‐ons facilitate the formation of carbamate salts . The exact base strength required is unclear due to steric effects and reactions of bases with CO 2 .…”

Catalytic Conversion of Carbon Dioxide through C-N Bond Formation

“…However, the carboxylative cyclization of allylamines and CO 2 would significantly expand the toolbox of 2-oxazolidinones synthesis. Most recently, Yu and co-workers summarized recent progress on this reaction by homogeneous catalysis in detail [60]. In addition, they also reviewed various cyclization reactions of allenic amines with CO 2 .…”