194156-25-7Relevant articles and documents
Copper(I)-catalyzed asymmetric alkene aziridination mediated by PhI(OAc)2: A facile one-pot procedure
Kwong, Hoi-Lun,Liu, Di,Chan, Ka-Yee,Lee, Chi-Sing,Huang, Ka-Hung,Che, Chi-Ming
, p. 3965 - 3968 (2004)
A facile one-pot procedure for copper-catalyzed PhI(OAc) 2-mediated asymmetric alkene aziridination had been developed. Commercially available PhI(OAc)2 and sulfonamides were used to generate the nitrene precursors (PhI=NR) in situ for olefin aziridination. This one-pot procedure had been optimized using 4-nitrobenzenesulfonamide as the nitrene source. With 5mol% of the chiral copper catalyst, these conditions afforded 94% yield of the isolated product with 75% ee. We had also developed a simple and rapid method to monitor the rate of this one-pot aziridination.
Stereoselective Lewis acid mediated (3+2) cycloadditions of N-H- and N-sulfonylaziridines with heterocumulenes
Craig, Robert A.,O'Connor, Nicholas R.,Goldberg, Alexander F. G.,Stoltz, Brian M.
supporting information, p. 4806 - 4813 (2014/05/06)
Alkyl and aryl isothiocyanates 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 stereoselec
On the enantioselectivity of aziridination of styrene catalysed by copper triflate and copper-exchanged zeolite Y: Consequences of the phase behaviour of enantiomeric mixtures of N-arene-sulfonyl-2-phenylaziridines
Jeffs, Laura,Arquier, Damien,Kariuki, Benson,Bethell, Donald,Page, Philip C. Bulman,Hutchings, Graham J.
scheme or table, p. 1079 - 1084 (2011/04/12)
By synthesising S-2-phenyl-N-(4-nitrophenyl)aziridine from S-phenylglycinol, it has been demonstrated that the aziridination of styrene by [N-(4-nitrobenzenesulfonyl)imino]phenyliodinane (nosyliminophenyliodinane, PhINNs) in the presence of S,S-2,2′-isopr
METAL PORPHYRIN CATALYZED OLEFIN AZIRIDINATION WITH SULFONYL AZIDES
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Page/Page column 47, (2009/12/27)
Cobalt(II) complex of P1 [Co(P1)], a new porphyrin that was designed on the basis of potential hydrogen bonding interactions in the metal-nitrene intermediate, is a highly active catalyst for olefin aziridination with azides. The [Co(P1)]- based system can be effectively employed for different combinations of aromatic olefins and arysulfonyl azides, synthesizing various sulfonylated aziridines in excellent yields. Besides its mild catalytic conditions, the Co-catalyzed aziridination process enjoys several attributes associated with the relatively low cost of cobalt and widely accessible arylsulfonyl azides. Furthermore, it generates stable dinitrogen as the only by-product.
Enantioselective syntheses of morpholines and their homologues via S N2-type ring opening of aziridines and azetidines with haloalcohols
Ghorai, Manas K.,Shukla, Dipti,Das, Kalpataru
supporting information; experimental part, p. 7013 - 7022 (2009/12/22)
(Chemical Equation Presented) A highly regio- and stereoselective strategy for the syntheses in high yield and enantioselectivity of a variety of substituted nonracemic morpholines and their homologues is described. The reaction proceeds via an SN2-type ring opening of activated aziridines and azetidines by suitable halogenated alcohols in the presence of Lewis acid followed by base-mediated intramolecular ring closure of the resulting haloalkoxy amine.
Asymmetric aziridination: A new entry to optically active non-N-protected aziridines
Kawabata, Hirotoshi,Omura, Kazufumi,Katsuki, Tsutomu
, p. 1571 - 1574 (2007/10/03)
A newly designed robust Ru(salen)(CO) complex 3 was found 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.
Catalytic asymmetric heterogeneous aziridination of styrene derivatives using bis(oxazoline)-modified Cu2+-exchanged zeolite Y
Ryan, Darragh,McMorn, Paul,Bethell, Donald,Hutchings, Graham
, p. 3566 - 3572 (2007/10/03)
The copper-catalysed aziridination of styrene derivatives using either Cu(OTf)2 as a homogeneous catalyst or copper-exchanged zeolite Y modified as a heterogeneous catalyst with bis(oxazoline) using [N-(p-nitrophenylsulfonyl)imino]phenyliodinane (PhI=NNs) as nitrene donor is described and discussed. For the homogeneously catalysed reaction virtually all the substituted derivatives gave lower yields of the aziridine with lower ee when compared with styrene, although 4-chlorostyrene did give enhanced ee. For the heterogeneous catalysed reaction the styrene derivatives often gave enhanced yield, particularly when the substituent was in the 4-position. Particularly high ee was observed for 2-chlorostyrene (95%) and 4-chlorostyrene (94%) and in general the ee observed for the heterogeneously catalysed reaction with the 2- and 4-substituted derivates was significantly higher than that for the equivalent homogeneously catalysed reaction. With copper-exchanged zeolite Y the leaching of Cu2+ into solution during reaction was much lower for the substituted styrene derivatives (0.4-7% of total Cu) than with styrene itself (10.3% of the total Cu). The effect of reaction time on aziridine yield reveals an S-shaped profile that is accentuated by the position of the substituent and this effect is observed for both the homogeneously catalysed pathway and the heterogeneously catalysed reaction. A series of competitive experiments in which styrene was co-reacted with equivalent quantities of 2-, 3- and 4-chlorostyrene revealed that the reaction of styrene enhanced by the other substrate, but the rate of reaction of the substituted styrene was decreased. Co-reaction of 2- and 4-chlorostyrene reveals interesting competitive effects, which are discussed in terms of the nature of the active site.
Design of a robust Ru(salen) complex: Aziridination with improved turnover number using N-arylsulfonyl azides as precursors
Omura, Kazufumi,Uchida, Tatsuya,Irie, Ryo,Katsuki, Tsatomu
, p. 2060 - 2061 (2007/10/03)
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)
Observation of the enhancement in enantioselectivity with conversion for the aziridination of styrene using copper bis(oxazoline) complexes
Gullick, John,Taylor, Sophia,Ryan, Darragh,McMorn, Paul,Coogan, Mike,Bethell, Donald,Bulman Page, Philip C.,Hancock, Frederick E.,King, Frank,Hutchings, Graham J.
, p. 2808 - 2809 (2007/10/03)
During the aziridination of styrene using copper bis(oxazoline) complexes the ee increases with conversion due to further reactions of the product.
Catalytic asymmetric heterogeneous aziridination of styrene using CuHY: Effect of nitrene donor on enantioselectivity
Taylor, Sophia,Gullick, John,McMorn, Paul,Bethell, Donald,Page, Philip C. Bulman,Hancock, Frederick E.,King, Frank,Hutchings, Graham J.
, p. 1714 - 1723 (2007/10/03)
The copper-catalysed aziridination of styrene with copper-exchanged zeolite Y (CuHY) and copper(II) triflate (trifluoromethanesulfonate) (Cu(OTf)2) as catalysts is described in detail. Two nitrene donors, [N-(p-tolylsulfonyl)imino)]phenyliodinane (PhI=NTs) and [N-(p-nitrophenylsulfonyl)imino]phenyliodinane (PhI=NNs) are compared. Modification of the catalyst with bis(oxazolines) affords enantioselective catalysts and a range of chiral bis-(oxazolines) has been studied. The ratio of nitrene donor to styrene is shown to be an important factor controlling both the yield and ee of aziridine formed. The best results are obtained with PhI=NNs; ee, ≥ 90%, together with high yields (≥ 85%), can readily be achieved with this nitrene donor using acetonitrile as solvent. Addition of the nitrene donor over a period of time, rather than all at the start of the reaction, is shown to enhance the yield of the aziridine but the ee is significantly decreased for both the homogeneous and the heterogeneous catalysts. Experiments in which the breakdown products of the nitrene donor, iodobenzene and the corresponding sulfonamide, are added at the star of the reaction show that a complex interplay exists at the copper active site between the reactants, products, chiral modifier and the solvent. However, the heterogeneous catalyst, CuHY, is found to give enhanced enantioselection for a range of bis(oxazolines) compared to the homogeneous catalyst, and the effect is considered to be due to the confinement of the catalyst within the micropores of the zeolite.
