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Herein, we have developed a rhodium-catalyzed C–H functionalization and subsequent intramolecular ring-opening/cyclization of vinylene carbonate with 2-pyrrolyl/indolylanilines, which leads to oxazolidinones in moderate to good yields. In this transformation, vinylene carbonate only eliminates one oxygen atom rather than –CO3 or CO2. Furthermore, some control experiments are conducted to elucidate the reaction mechanism. [ABSTRACT FROM AUTHOR]

CO2‐transformations into high value‐added products have become a fascinating area in green chemistry. Herein, a Ru(III)‐porphyrin catalyst (RuCl3 ⋅ 3H2O−H2TPP) was found highly efficient in the three‐component reaction of CO2, aliphatic amines and dichloroethane (or its derivative) for synthesis of oxazolidinones in the yields of 71∼91%. It was indicated by means of the control experiments and UV‐vis spectra that CO2 was stoichiometrically activated by the involved aliphatic amine substrates to form a stable carbamate salt while 1,2‐dichloroethane (or its derivative) was independently activated by the involved Ru(III)‐porphyrin catalyst. The combination of CO2‐activation by aliphatic amines with 1,2‐dichloroethane activation by Ru(III)‐porphyrin catalyst cooperatively contributed to this successful transformation. [ABSTRACT FROM AUTHOR]

An efficient convenient procedure for the synthesis of 3-aryl-2-oxazolidinones from 2-(arylamino) alcohols and diethyl carbonate (DEC) catalyzed by ionic liquids is described. The effects of reaction time, amount of catalyst and temperature were investigated. Excellent yields of products were obtained under the optimized reaction conditions, when using BmimOAc as a catalyst. An intermediate ethyl 2-(phenyl amino) ethyl carbonate was isolated and characterized. 1 H NMR spectroscopy and DFT calculations indicated that BmimOAc cooperatively activate the substrates through hydrogen bonding with its anion and cation sites. According to these results, a possible reaction mechanism was discussed. [ABSTRACT FROM AUTHOR]

Highly Z-selective syntheses of oxazolidin-2-ones from propargylic alcohols containing internal alkynes and phenyl isocyanate were achieved by using a combination of silver acetate and N,N-dimethylaminopyridine. The catalytic system was applied to propargylic alcohols containing alkyl-substituted alkyne groups. By considering the results in the presence and absence of an electron-withdrawing group on the aromatics, it was shown that the silver catalyst effectively activates the C=C triple bond by acting as a π-Lewis acid to produce the corresponding oxazolidinones with high Z-selectivities. [ABSTRACT FROM AUTHOR]

A new synthetic method for enantioselective synthesis of syn or anti-3-amino-3-aryl-1,2-alkanediols via proline catalyzed α-aminooxylation of β-amino aldehydes are described. This methodology is successfully applied to a concise and protecting group-free asymmetric synthesis of (-)-cytoxazone, (+)-epi-cytoxazone and formal synthesis of N-thiolated 2-oxazolidinone. [ABSTRACT FROM AUTHOR]

Abstract: A series of polyethylene glycol (PEG)-functionalized ionic liquids (ILs) were developed as recyclable and efficient catalysts for selective synthesis of 5-aryl-2-oxazolidinones from aziridines and CO2 without addition of any organic solvents or additives. In particular, high yields, chemo- and regio-selectivities of oxazolidinones were attained when BrDBNPEG150DBNBr (DBN: 1,5-diazabicyclo[4.3.0]non-5-ene) was used as the catalyst, presumably due to activation of CO2 by the ether linkage in the PEG backbone, and stabilization of the ring-opened species of aziridine by the delocalized cation BrDBNPEG150DBN+. Furthermore, the catalyst could be reused for over four consecutive cycles without appreciable loss of catalytic activity and selectivity. The effects of catalyst structure and various reaction parameters on the catalytic performance were also investigated in detail. It was demonstrated that the catalyst worked well for a variety of aziridines producing the corresponding oxazolidinones in good yields and excellent regio-selectivities. Therefore, this solvent-free process could thus represent an environmentally friendly approach for ILs-catalyzed conversion of CO2 into value-added chemicals. [Copyright &y& Elsevier]

A highly efficient and stereoselective cycloaddition of aryl isocyanates with chiral oxiranes catalyzed by MgI2 etherate under solvent-free conditions was developed to prepare the chiral oxazolidinone derivatives. This methodology has been applied into the practical synthesis of antibacterial drug linezolid. [ABSTRACT FROM AUTHOR]

The article discusses a study on a selective route for the synthesis of 5-substituted oxazolidin-2-ones via a N-heterocyclic carbene (NHC) catalyzed carbon dioxide insertion to N-tosyl aziridines. The study demonstrated that this catalyst system is effective for the cycloaddition of carbon dioxide to 1,2,3-trisubstituted aziridines forming the corresponding 3,4,5-trisubstituted oxazolidin-2-ones with high regio and stereoselectivity. Also cited are other catalysts for aziridine carboxylation.

Abstract: CuI/N,N-dimethylglycine catalyzed coupling of aryl bromides with substituted oxazolidinones took place at 120°C in DMF, affording the corresponding N-arylation products with good to excellent yields. A number of functional groups, such as ketone, nitrile, nitro, methoxy, and hydroxyl were tolerated under these conditions, thereby allowing diversity synthesis of N-aryloxazolidinones. [Copyright &y& Elsevier]

A diagram is presented which explains the chemical process of multiple absolute Stereocontrol in Pd-Catalyzed [3 + 2] Ccycloaddition of Oxazolidinones and Trisubstituted Alkenes using Chiral Ammonium-Phosphine Hybrid Ligands.

The reaction has a broad substrate scope, thus tolerating functionalized aryl and alkyl substituted epoxides and arylisocyanates, but no alkyl isocyanates. [ABSTRACT FROM AUTHOR]

Various oxazole derivatives are synthesized by carboxylative cyclization of propargylic amines with CO2 using a Cu(II)-substituted polyoxometalate-based ionic liquid as catalyst. [ABSTRACT FROM AUTHOR]

The Al-catalyzed reaction of epoxides with phenyl carbamate affords stereoselectively oxazolidinones, which are readily transformed into non-symmetrical ureas by reaction with amines. [ABSTRACT FROM AUTHOR]

The reaction of carbon dioxide with propargylic amines is promoted by a protic ionic liquid such as 1,8-diazabicyclo[5.4.0]-7-undecenium 2-methylimidazolide (DBM) that acts also as a solvent to give the corresponding oxazolidinones in high yields. [ABSTRACT FROM AUTHOR]

Several organosilicon agents are evaluated in view of their synergistic combination with fluoride, and cyclodimethylsiloxane is found to deliver increased product yields compared to tetrabutylammonium difluorotriphenyl silicate for certain substrates. [ABSTRACT FROM AUTHOR]

In the most cases the reaction gives both regioisomers, but only the major isomer is isolated. [ABSTRACT FROM AUTHOR]

The authors present chemical equations related to the allylic amination for the syntheses of α,β-unsaturated γ-amino esters catalyzed by iridium catalyst via regiospecific and stereospecific reactions and formation of oxazolidin-2-ones published in the "Chemical Science" in 2013.