Nosylaziridines are highly reactive electrophiles towards a variety of nucleophiles yielding the corresponding SN2 adducts without competing attack on the nosyl functionality (SNAr). The resulting primary nosylamide adducts can be readily cleaved under mild conditions to provide the primary amines. (C) 1997 Elsevier Science Ltd.
Stereoselective Lewis Acid Mediated (3+2) Cycloadditions of<i>N</i>-H- and<i>N</i>-Sulfonylaziridines with Heterocumulenes
作者:Robert A. Craig、Nicholas R. O'Connor、Alexander F. G. Goldberg、Brian M. Stoltz
DOI:10.1002/chem.201303699
日期:2014.4.14
Alkyl and arylisothiocyanates and carbodiimides are effective substrates in (3+2) cycloadditions with N‐sulfonyl‐2‐substituted aziridines and 2‐phenylaziridine for the synthesis of iminothiazolidines and iminoimidazolidines. Additionally, the stereoselective (3+2) cycloaddition of N‐H‐ and N‐sulfonylaziridines with isothiocyanates can be accomplished, allowing for the synthesis of highly enantioenriched
to catalyze asymmetric aziridination using azide compounds carrying p-nitrobenzenesulfonyl and 2-(trimethylsilyl)ethanesulfonyl (SES) groups, which are easily removable N-protecting groups under mild conditions, as a nitrene precursor in a highly enantioselective manner. In particular, the reactions with SES azide showed excellent enantioselectivity greater than 90% ee, except for one example.
Design of a robust Ru(salen) complex: aziridination with improved turnover number using N-arylsulfonyl azides as precursorsElectronic supplementary information (ESI) available: typical experimental procedures, determination of enantiomeric excess and elementary analysis for complexes 3 and 5. See http://www.rsc.org/suppdata/cc/b4/b407693a/
A new robust fluorinated (OC)Ru(salen) complex was designed on the basis of an X-ray structure of its parent complex to show improved turnover numbers (up to 878) and enantioselectivities (up to 99%) in aziridination reactions using p-toluenesulfonyl (Ts) or p-nitrobenzenesulfonyl (Ns) azide as the nitrene precursor; the latter is synthetically advantageous since the Ns group is N-protecting and can
Enantiospecific and regioselective opening of 2-alkyl nosylaziridines by indoles mediated by boron trifluoride. Application to a practical synthesis of a GnRH antagonist
作者:Roger N Farr、Ramon J Alabaster、John Y.L Chung、Bridgette Craig、John S Edwards、Andrew W Gibson、Guo-Jie Ho、Guy R Humphrey、Simon A Johnson、E.J.J Grabowski
DOI:10.1016/j.tetasy.2003.08.038
日期:2003.11
An efficient, high yield process for the synthesis of a GnRH antagonist has been developed. We have demonstrated that under boron trifluoride mediation, nosyl aziridines will react with 2-arylindole derivatives to afford β-substituted tryptamines in an enantiospecific process with remarkably high regioselectivity. The scope of the reaction was explored with several 2-substituted nosyl aziridines. The
A Synthetic Route to Chiral Tetrahydropyrroloindoles via Ring Opening of Activated Aziridines with 2-Bromoindoles Followed by Copper-Catalyzed C–N Cyclization
作者:Masthanvali Sayyad、Abhijit Mal、Imtiyaz Ahmad Wani、Manas K. Ghorai
DOI:10.1021/acs.joc.6b01049
日期:2016.8.5
A new syntheticroute to nonracemic tetrahydropyrrolo[2,3-b]indoles has been developed via SN2-type ringopening of enantiopure N-activated aziridines with 2-bromoindoles followed by copper-catalyzed C–Ncyclization. A series of N-activated aziridines and 2-bromoindole derivatives with different substitution patterns were studied to afford the corresponding tetrahydropyrrolo[2,3-b]indoles in good yields
通过用2-溴吲哚将对映纯N活化的氮丙啶的S N 2型开环,然后进行铜催化的CN环化,已开发出一种新的合成非外消旋四氢吡咯并[2,3- b ]吲哚的途径。研究了一系列具有不同取代模式的N活化氮丙啶和2-溴吲哚衍生物,从而以良好的收率和优异的ee(高达99%)提供了相应的四氢吡咯并[2,3- b ]吲哚。高度取代的四氢吡咯并[2,3- b ]吲哚由对映体纯的反式-二取代的氮丙啶合成为单个立体异构体(de,ee> 99%)。