Br(?)nsted Base Catalyzed Synthesis Of Oxazolidinone With Internal Propargylic Alcohols And Isocyanates

Oxazolidinone and its derivatives are very important heterocyclic compounds in the pharmaceutical, agricultural chemicals, polymers, and have a very wide range of applications in organic synthesis. The majority of reported synthetic methods were using metal catalysts, and the scope of substrates was not wide. Therefore, the development of more efficient synthetic methods of oxazolidinones makes a very important significance.This thesis mainly introduces the synthesis of multisubstituted oxazolidinone with propargyl alkynols and isocyanates. First, a one-pot cascade reaction of Bronsted base promoted cyclization of synthesis of oxazolidin-2-ones with internal propargylic alcohols and isocyanates under magnetic stirring condition is presented. The selectivity is conformed by the DFT calculation. The amount of E isomer can be increased by acid-promoted isomerization. The transformations are high yielding, atom-efficient, metal free and environmentally benign in terms of the substrates and reagents being used. Subsequently, under sonication this reaction can be performed in a lower equivalent of base and yield more of the product in a shorter time.This thesis realized the one-pot synthesis of poly-substituted oxazolidinone with internal propargyl alcohol and isocyanate. All new products are all confirmed by NMR and HRMS and some crucial structures are confirmed by X-ray.