Synthesis of Functionalized Thiazolidin-2-imine and Oxazolidin-2-one Derivatives from p-Quinamines via [3 + 2] Annulation of Isothiocyanates and CO₂

Abstract

An efficient and environmentally friendly synthetic approach to prepare thiazolidine-2-imine and oxazolidine-2-one derivatives has been developed. Thiazolidine-2-imines are synthesized in good to excellent yields by [3 + 2] annulation of pquinamines with isothiocyanates under catalyst-and solvent-free conditions. Oxazolidine-2-ones are produced in good to excellent yields via [3 + 2] annulation of p-quinamines with CO 2 using triethylenediamine (DABCO) as an organocatalyst. Furthermore, this strategy can be performed on a gram scale and tolerate a wide range of functional groups. Article pubs.acs.org/joc

Phosphomolybdic acid supported on magnetic poly calix[4]resorcinarene-EDTA-chitosan network as a recyclable catalyst for the synthesis of 5-aroyl-NH-1,3-oxazolidine-2-ones

“… Entry Catalyst Reaction condition Solvent Time (h) Yield (%) Ref. 1 CoFe 2 O 4 @calix-EDTA-Cs@PMA Sonication/50 °C PEG-400 30 min 95 This work 2 HNTf 2 r.t DCM 55 62 42 3 NaH 25–30 °C DCM//DMF 9 92 43 4 ClCO 2 CH 3 Reflux CH 3 CN 12 87 44 5 MCPBA 65 °C THF/DMF 4 84 45 …”