A range of N-arylaziridines were prepared by the palladium or copper catalyzed amination reaction between N-H aziridines and aryl bromides or arylboronic acids. These results showcase the synthetic utility of metal-bound aziridine species in nitrogen transfer processes.
The Development of Scalemic Multidentate Niobium Complexes as Catalysts for the Highly Stereoselective Ring Opening of <i>meso</i>-Epoxides and <i>meso</i>-Aziridines
作者:Kenzo Arai、Simone Lucarini、Matthew M. Salter、Kentaro Ohta、Yasuhiro Yamashita、Shū Kobayashi
DOI:10.1021/ja0708666
日期:2007.7.1
found to be most convenient to conduct the reactions with 10 mol % catalyst loading at 0.16 M, at higher overall concentration the reaction still proceeded efficiently with as little as 0.25 mol % catalyst to give the desired products with no significant reduction in yields or enantioselectivities. In addition, the current catalyst system was also found to mediate the asymmetric ring opening of nonsymmetrical
Cationic palladium and nickel complexes have been found to catalyze the ring-opening of meso-N-aryl aziridines with anilines very efficiently and furnish valuable 1,2-diamines in typically excellent yields. The active catalysts were generated in situ from the corresponding metal dichloride bis(triphenylphosphine) complexes through chloride abstraction with a silver salt. This new protocol is applicable across a broad substrate range with both cyclic as well as acyclic aziridines. In addition, cationic gold-phosphine complexes proved to be highly reactive as well as delivering products in comparable rates and yields.
Indium(III) chloride efficiently catalyzed the thiol addition to meso-aziridines at very low substrate-catalyst ratios giving rise to 1,2-amino sulfides in excellent yields and complete diastereocontrol. (c) 2007 Elsevier Ltd. All rights reserved.
The Ti-BINOLate-catalyzed, enantioselective ring-opening of meso-aziridines with amines
The titanium-BINOLate-catalyzed, highly enantioselective ring-opening reaction of meso-aziridines has been developed which furnishes trans-1,2-diamines in typically good yields and excellent enantioselectivities. N-Aryl aziridines attached to a 5- or 6-membered carbocyclic ring are among the best substrates for this process providing the products in up to >99% ee. The chiral catalyst is easily prepared in situ from commercially available components and does not require any laborious ligand synthesis. Structural investigations into the catalyst composition reveal an oligomeric structure of the active Ti-complex.
A range of N-arylaziridines were prepared by the palladium or copper catalyzed amination reaction between N-H aziridines and aryl bromides or arylboronic acids. These results showcase the synthetic utility of metal-bound aziridine species in nitrogen transfer processes.