1240306-07-3Relevant academic research and scientific papers
Multifaceted interception of 2-chloro-2-oxoacetic anhydrides: A catalytic asymmetric synthesis of β-lactams
Huang, Li,Zhao, Wenjun,Staples, Richard J.,Wulff, William D.
, p. 622 - 628 (2013)
Aziridine-2-carboxylic acids will react with oxalyl chloride to give morpholin-2,3,5-trionones, cyclic N-carboxyanhydrides or β-lactams depending on the nature of the substituent at the 3-position. All substrates can be diverted to β-lactams upon treatment with a Vilsmeier reagent. The three to four membered ring expansion is stereospecific and proceeds with high yields and diastereoselection. This method provides for an asymmetric synthesis of β-lactams from simple aldehydes via a multi-component catalytic asymmetric aziridination reaction. The Royal Society of Chemistry 2013.
Multicomponent catalytic asymmetric aziridination of aldehydes
Gupta, Anil K.,Mukherjee, Munmun,Wulff, William D.
supporting information; experimental part, p. 5866 - 5869 (2011/12/15)
The first multicomponent catalytic asymmetric aziridination reaction is developed to give aziridine-2-carboxylic esters with very high diastereo- and enantioselectivity from aromatic and aliphatic aldehydes. This new method pushes the boundary of the aziridination reaction to substrates that failed with preformed imines.
Seeking passe-partout in the catalytic asymmetric aziridination of imines: Evolving toward substrate generality for a single chemzyme
Mukherjee, Munmun,Gupta, Anil K.,Lu, Zhenjie,Zhang, Yu,Wulff, William D.
experimental part, p. 5643 - 5660 (2010/11/18)
The asymmetric catalytic aziridination reaction (AZ reaction) of imines derived from dianisylmethyl (DAM) amine and tetra-methyldianisylmethyl (MEDAM) amine were examined with boroxinate catalysts prepared from both the VANOL and VAPOL ligands. This included an evaluation of different protocols for the preparation of the catalyst. The AZ reaction of DAM and MEDAM imines prepared from nine different aryl and aliphatic aldehydes were examined. The MEDAM imines were superior to the DAM imines in the AZ reaction, giving much higher asymmetric inductions and higher overall yields of aziridines. The MEDAM imines were found to also be superior to the previously studied diphenylmethyl (benzhydryl or Bh) and tetra-tert-butyldianisylmethyl (BUDAM) imines especially for imines derived from aliphatic aldehydes. The average asymmetric induction over the nine different MEDAM imines studied was 97% ee with the VAPOL catalyst and 96% ee with the VANOL catalyst. The MEDAM imines can be deprotected to give N-H aziridines in all cases except for some electron-rich aryl aldehydes. The MEDAM imines are much more reactive than benzhydryl imines, and this was most evident when a diazoacetate ester is replaced by a diazoacetamide. The less reactive diazoacetamides give very low yields in their reactions with benzhydryl imines but high yields with MEDAM imines.
Substrate-induced covalent assembly of a chemzyme and crystallographic characterization of a chemzyme-substrate complex
Hu, Gang,Gupta, Anil K.,Huang, Rui H.,Mukherjee, Munmun,Wulff, William D.
supporting information; experimental part, p. 14669 - 14675 (2010/12/25)
A substrate induced covalent assembly of a highly organized chemzyme known to be effective in both catalytic asymmetric aziridination and aza Diels-Alder reactions is described and the information gained from which led to an efficient one-pot aziridination protocol. The crystal structures of two chemzyme-iminium complexes were elucidated by X-ray diffraction analysis that provides critical insights into the binding of the substrates with the chemzyme.
