1121-83-1Relevant academic research and scientific papers
Aluminium-Catalysed Oxazolidinone Synthesis and their Conversion into Functional Non-Symmetrical Ureas
Laserna, Victor,Guo, Wusheng,Kleij, Arjan W.
, p. 2849 - 2854 (2015/09/28)
An efficient and practical aluminium-catalysed approach towards a range of functional oxazolidinones is reported. The method is based on cheap and readily available starting materials including terminal and internal (bicyclic) epoxides and phenyl carbamate. The oxazolidinones serve as highly useful synthons for the high yield preparation of non-symmetrical ureas by nucleophilic ring-opening affording the targeted urea compounds with excellent functional group diversity, high regioselectivity and isolated yields up to >99%.
Tetramic acid derivatives via Ugi-Dieckmann-reaction
Spatz, Julia H.,Welsch, Sebastian J.,Duhaut, David-Emmanuel,J?ger, Nadine,Boursier, Thomas,Fredrich, Martin,Allmendinger, Lars,Ross, Günther,Kolb, Jürgen,Burdack, Christoph,Umkehrer, Michael
experimental part, p. 1705 - 1707 (2009/09/05)
Tetramic acid derivatives constitute an important class of nitrogen containing heterocycles, and are key structural motifs in many natural products of terrestrial and marine origin. The interesting biological and structural diversity of this class of subs
De novo synthesis of troc-protected amines: Intermolecular rhodium-catalyzed C-H amination with N-tosyloxycarbamates
Lebel, Helene,Kim, Huard
, p. 639 - 642 (2008/02/03)
The rhodium-catalyzed intermolecular C-H insertion of the nitrene derived from 2,2,2-trichloroethyl-N-tosyloxycarbamate proceeded in good to excellent yields to produce a variety of Troc-protected amines. With cyclic aliphatic alkanes, it is possible to use only 2 equiv of substrate, whereas the reaction with aromatic alkanes is run neat. Not only does the nitrene insertion proceed in benzylic, secondary, and tertiary C-H bonds but also primary C-H insertion products were obtained in good yields. Finally, the use of chiral rhodium catalysts to provide an enantioselective version of this process is discussed.
N-acyl-5,5-dimethyloxazolidin-2-ones as latent aldehyde equivalents
Bach, Jordi,Blachere, Cecile,Bull, Steven D.,Davies, Stephen G.,Nicholson, Rebecca L.,Price, Paul D.,Sanganee, Hitesh J.,Smith, Andrew D.
, p. 2001 - 2010 (2007/10/03)
A study of the properties of N-hydrocinnamoyl- derivatives of 5,5-dimethyloxazolidin-2-one, 4,4-dimethyloxazolidin-2-one and oxazolidin-2-one upon hydride reduction with DIBAL-H demonstrates that the 5,5-dimethyl-group is essential for inhibition of endocyclic nucleophilic attack. For instance, treatment of N-hydrocinnamoyl-5,5-dimethyl-oxazolidin-2-one with DIBAL-H results in the selective formation of the stable N-1′-hydroxyalkyl derivative which may be regarded as a masked hydrocinnamaldehyde equivalent, as treatment under basic conditions affords the parent aldehyde in excellent yield. Treatment of N-hydrocinnamoyl-4,4-dimethyloxazolidin-2-one with DIBAL-H under identical conditions affords a complex mixture of products, including the formate ester product of endocyclic cleavage. As an alternate strategy, DIBAL-H reduction of straight chain and branched N-acyl-5,5-dimethyloxazolidin-2-one derivatives, followed by a Horner-Wadsworth-Emmons reaction affords α,β-unsaturated esters in good yields. Branching α- to the exocyclic carbonyl in N-acyl-oxazolidinones inhibits DIBAL-H reduction, but this can be overcome by precomplexation with ZnCl2, with subsequent fragmentation generating either the corresponding aldehyde or α,β-unsaturated esters. The addition of ZnCl2 has been shown to increase the diastereoselectivity observed in Wadsworth-Horner-Emmons reactions of lithiated phosphonates.
