1499-00-9Relevant articles and documents
Anomalous nuclear overhauser effects in carbon-substituted aziridines: Scalar cross-relaxation of the first kind
Kuprov, Ilya,Hodgson, David M.,Kloesges, Johannes,Pearson, Christopher I.,Odell, Barbara,Claridge, Timothy D. W.
, p. 3697 - 3701 (2015)
Anomalous NOESY cross-peaks that cannot be explained by dipolar cross-relaxation or chemical exchange are described for carbon-substituted aziridines. The origin of these is identified as scalar cross-relaxation of the first kind, as demonstrated by a com
A pathway for NH addition to styrene promoted by gold
Deng, Xingyi,Baker, Thomas A.,Friend, Cynthia M.
, p. 7075 - 7078 (2006)
(Figure Presented) Going for gold! The synthesis of aziridines using heterogeneous gold catalysts has an unanticipated potential. Chemisorbed atomic oxygen is used to activate ammonia, producing NH bound to the gold surface (see scheme). Addition of NH ac
Catalyst-Free Electrophilic Ring Expansion of N-Unprotected Aziridines with α-Oxoketenes to Efficient Access 2-Alkylidene-1,3-Oxazolidines
Chen, Xingpeng,Huang, Zhengshuo,Xu, Jiaxi
supporting information, p. 3098 - 3108 (2021/05/10)
2-(2-Oxoalkylidene)-1,3-oxazolidine derivatives were synthesized in good to excellent yields regiospecifically through the catalyst-free electrophilic ring expansion of N-unprotected aziridines and the ketene C=O double bond of α-oxoketenes, in situ generated from the microwave-assisted Wolff rearrangement of 2-diazo-1,3-diketones. The ring expansion predominantly underwent an SN1 process and the hydrogen bond decides the (E)-configuration of products. (Figure presented.).
Structure and Reactivity of a Manganese(VI) Nitrido Complex Bearing a Tetraamido Macrocyclic Ligand
Shi, Huatian,Lee, Hung Kay,Pan, Yi,Lau, Kai-Chung,Yiu, Shek-Man,Lam, William W. Y.,Man, Wai-Lun,Lau, Tai-Chu
supporting information, p. 15863 - 15872 (2021/09/30)
Manganese complexes in +6 oxidation state are rare. Although a number of Mn(VI) nitrido complexes have been generated in solution via one-electron oxidation of the corresponding Mn(V) nitrido species, they are too unstable to isolate. Herein we report the isolation and the X-ray structure of a Mn(VI) nitrido complex, [MnVI(N)(TAML)]- (2), which was obtained by one-electron oxidation of [MnV(N)(TAML)]2- (1). 2 undergoes N atom transfer to PPh3 and styrenes to give Ph3P═NH and aziridines, respectively. A Hammett study for various p-substituted styrenes gives a V-shaped plot; this is rationalized by the ability of 2 to function as either an electrophile or a nucleophile. 2 also undergoes hydride transfer reactions with NADH analogues, such as 10-methyl-9,10-dihydroacridine (AcrH2) and 1-benzyl-1,4-dihydronicotinamide (BNAH). A kinetic isotope effect of 7.3 was obtained when kinetic studies were carried out with AcrH2 and AcrD2. The reaction of 2 with NADH analogues results in the formation of [MnV(N)(TAML-H+)]- (3), which was characterized by ESI/MS, IR spectroscopy, and X-ray crystallography. These results indicate that this reaction occurs via an initial "separated CPET"(separated concerted proton-electron transfer) mechanism; that is, there is a concerted transfer of 1 e- + 1 H+ from AcrH2 (or BNAH) to 2, in which the electron is transferred to the MnVI center, while the proton is transferred to a carbonyl oxygen of TAML rather than to the nitrido ligand.
Enantioselective Aminohydroxylation of Styrenyl Olefins Catalyzed by an Engineered Hemoprotein
Cho, Inha,Prier, Christopher K.,Jia, Zhi-Jun,Zhang, Ruijie K.,G?rbe, Tamás,Arnold, Frances H.
supporting information, p. 3138 - 3142 (2019/02/01)
Chiral 1,2-amino alcohols are widely represented in biologically active compounds from neurotransmitters to antivirals. While many synthetic methods have been developed for accessing amino alcohols, the direct aminohydroxylation of alkenes to unprotected, enantioenriched amino alcohols remains a challenge. Using directed evolution, we have engineered a hemoprotein biocatalyst based on a thermostable cytochrome c that directly transforms alkenes to amino alcohols with high enantioselectivity (up to 2500 TTN and 90 % ee) under anaerobic conditions with O-pivaloylhydroxylamine as an aminating reagent. The reaction is proposed to proceed via a reactive iron-nitrogen species generated in the enzyme active site, enabling tuning of the catalyst's activity and selectivity by protein engineering.
