160424-29-3Relevant articles and documents
Carbon dioxide as a carbonylating agent in the synthesis of 2-oxazolidinones, 2-oxazinones, and cyclic ureas: Scope and limitations
Paz, Jairo,Perez-Balado, Carlos,Iglesias, Beatriz,Munoz, Luis
experimental part, p. 3037 - 3046 (2010/07/15)
Carbon dioxide can be used as a convenient carbonylating agent in the synthesis of 2-oxazolidinones, 2-oxazinones, and cyclic ureas. The transient carbamate anion generated by treating a primary or secondary amine group in basic media can be activated with phosphorylating agents such as Diphenylphosphoryl azide (DPPA) and Diphenyl chlorophosphate (DPPCl) but also with other types of electrophiles such as SOCl2, TsCl, or AcCl. The intramolecular trapping of the activated carbamate by a hydroxyl group leads to the formation of 2-oxazolidinones or 2-oxazinones in good to excellent yields. This methodology was successfully applied to the synthesis of cyclic ureas up to 7-membered rings from the corresponding diamines.
Carbonylation with CO2 and phosphorus electrophiles: A convenient method for the synthesis of 2-oxazolidinones from 1,2-amino alcohols
Paz, Jairo,Pérez-Balado, Carlos,Iglesias, Beatriz,Mu?oz, Luis
scheme or table, p. 395 - 398 (2009/08/09)
2-Oxazolidinones were prepared in good yields from 1,2-amino alcohols and CO2 in the presence of tetramethyl-phenylguanidine (PhTMG) as a base and a variety of phosphorus electrophiles under mild conditions. This procedure is advantageous over previous methodologies and relies on a novel carbonylation procedure that utilizes nontoxic CO2 and phosphorus electrophiles. Georg Thieme Verlag Stuttgart.
Fluorinated chiral secondary amines as catalysts for epoxidation of olefins with oxone
Ho, Chun-Yu,Chen, Ying-Chun,Wong, Man-Kin,Yang, Dan
, p. 898 - 906 (2007/10/03)
(Chemical Equation Presented) We have synthesized a series of chiral cyclic secondary amines having different substitution patterns and have screened them as catalysts for the asymmetric epoxidation of olefins using Oxone. The highest enantiomeric excess (61%) occurred for the epoxidation of 1-phenylcyclohexene catalyzed by a secondary amine bearing a fluorine atom at the β-position relative to the amino center. Our experimental results provide further support to the notion that the amine plays a dual role - as a phase transfer catalyst and an Oxone activator - in these epoxidation reactions. The slightly acidic reaction conditions we employed in this work obviate the need to preform ammonium salts, which are the actual catalysts that mediate the epoxidations.