1131-40-4Relevant articles and documents
Characterization of a Cyanobacterial Haloperoxidase and Evaluation of its Biocatalytic Halogenation Potential
Frank, Annika,Seel, Catharina Julia,Groll, Michael,Gulder, Tanja
, p. 2028 - 2032 (2016)
Vanadium-dependent haloperoxidases (VHPOs) are a class of halogenating enzymes found in fungi, lichen, algae, and bacteria. We report the cloning, purification, and characterization of a functional VHPO from the cyanobacterium Acaryochloris marina (AmVHPO), including its structure determination by X-ray crystallography. Compared to other VHPOs, the AmVHPO features a unique set of disulfide bonds that stabilize the dodecameric assembly of the protein. Easy access by high-yield recombinant expression, as well as resistance towards organic solvents and temperature, together with a distinct halogenation reactivity, make this enzyme a promising starting point for the development of biocatalytic transformations.
Vanadium-catalyzed oxidative bromination under atmospheric oxygen
Kikushima, Kotaro,Moriuchi, Toshiyuki,Hirao, Toshikazu
, p. 1213 - 1216 (2009)
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Discrete spherical hexadecavanadates incorporating a bromide with oxidative bromination activity
Kato, Naohiro,Hayashi, Yoshihito
, p. 11804 - 11811 (2013)
Two discrete hexadecavanadates, (n-Bu4N)4[V 16O38(X)] (X = Cl- (1) and X = Br- (2)), were synthesized by a reaction of [V10O26] 4- with a template anion resulting in the incorporation of chloride or bromide in the {V16} spherical cluster framework. The reaction of [V 10O26]4- with p-toluenesulfonic acid proceeded under an aerobic environment to give 2 in the presence of an excess amount of bromide anion, which acted as both a template anion and a reducing reagent for the formation of the mixed-valence framework. For the synthesis of cluster 1, additional reductive conditions were required due to the weak reducing ability of the chloride anion. The crystal structures of 1 and 2 were determined using single-crystal X-ray diffraction analysis. Both were found to consist of a discrete [VV9VIV7O 38(X)]4- framework by the linkage of VO5 pyramidal units. Cyclic voltammetric studies of 1 and 2 in acetonitrile showed a series of stepwise reversible redox processes, which were due to the redox of the spherical polyoxovanadate frameworks. The oxidative bromination reactions of aromatic substrates were also investigated using cluster 2 as a catalyst under aerobic conditions. The Royal Society of Chemistry.
Indole-Catalyzed Bromolactonization in Lipophilic Solvent: A Solid-Liquid Phase Transfer Approach
Chen, Tao,Foo, Thomas Jian Yao,Yeung, Ying-Yeung
, p. 4751 - 4755 (2015)
We have developed a novel indole-catalyzed bromolactonization of olefinic acids. The reaction could be conducted in lipophilic solvent through a solid-liquid phase transfer mechanism. This catalytic protocol has been applied to the synthesis of base-sensitive bromolactones. (Chemical Equation Presented).
Hydrogen-Bond-Donor Solvents Enable Catalyst-Free (Radio)-Halogenation and Deuteration of Organoborons
Yang, Yi,Gao, Xinyan,Zeng, Xiaojun,Han, Junbin,Xu, Bo
supporting information, p. 1297 - 1300 (2020/12/23)
A hydrogen bond donor solvent assisted (radio)halogenation and deuteration of organoborons has been developed. The reactions exhibited high functional group tolerance and needed only an ambient atmosphere. Most importantly, compared to literature methods, our conditions are more consistent with the principals of green chemistry (e.g., metal-free, strong oxidant-free, more straightforward conditions).
Stepwise mechanism for the bromination of arenes by a hypervalent iodine reagent
Arrieta, Ana,Cossío, Fernando P.,Granados, Albert,Shafir, Alexandr,Vallribera, Adelina
, p. 2142 - 2150 (2020/03/11)
A mild, metal-free bromination method of arenes has been developed using the combination of bis(trifluoroacetoxy)iodobencene and trimethylsilyl bromide. In situ-formed dibromo(phenyl)-λ3-iodane (PhIBr2) is proposed as the reactive intermediate. This methodology using PIFA/TMSBr has been applied with success to a great number of substrates (25 examples). The treatment of mono-substituted activated arenes led to para-brominated products (2u-z) in excellent 83-96% yields. Density functional theory calculations indicate a stepwise mechanism involving a double bromine addition followed by a type II dyotropic reaction with concomitant re-aromatization of the six-membered ring.