61592-47-0Relevant academic research and scientific papers
Cross-Linked Artificial Enzyme Crystals as Heterogeneous Catalysts for Oxidation Reactions
Lopez, Sarah,Rondot, Laurianne,Leprêtre, Chloé,Marchi-Delapierre, Caroline,Ménage, Stéphane,Cavazza, Christine
supporting information, p. 17994 - 18002 (2017/12/26)
Designing systems that merge the advantages of heterogeneous catalysis, enzymology, and molecular catalysis represents the next major goal for sustainable chemistry. Cross-linked enzyme crystals display most of these essential assets (well-designed mesoporous support, protein selectivity, and molecular recognition of substrates). Nevertheless, a lack of reaction diversity, particularly in the field of oxidation, remains a constraint for their increased use in the field. Here, thanks to the design of cross-linked artificial nonheme iron oxygenase crystals, we filled this gap by developing biobased heterogeneous catalysts capable of oxidizing carbon-carbon double bonds. First, reductive O2 activation induces selective oxidative cleavage, revealing the indestructible character of the solid catalyst (at least 30 000 turnover numbers without any loss of activity). Second, the use of 2-electron oxidants allows selective and high-efficiency hydroxychlorination with thousands of turnover numbers. This new technology by far outperforms catalysis using the inorganic complexes alone, or even the artificial enzymes in solution. The combination of easy catalyst synthesis, the improvement of "omic" technologies, and automation of protein crystallization makes this strategy a real opportunity for the future of (bio)catalysis.
Difunctionalization of Alkenes Using 1-Chloro-1,2-benziodoxol-3-(1H)-one
Egami, Hiromichi,Yoneda, Takahiro,Uku, Minako,Ide, Takafumi,Kawato, Yuji,Hamashima, Yoshitaka
, p. 4020 - 4030 (2016/06/09)
Difunctionalization of alkenes with 1-chloro-1,2-benziodoxol-3-(1H)-one (1) was investigated. Various additional nucleophiles were tested, and oxychlorination, dichlorination, azidochlorination, chlorothiocyanation, and iodoesterfication were demonstrated. The oxychlorination product was obtained efficiently when the reaction was operated in water. Dichlorination occurred in the presence of a Lewis basic promoter, such as 4-phenylpyridine N-oxide, as an additive. The reaction with in situ-generated azido anion afforded azidochlorinated compounds with a chlorine atom at the terminal position, while the reaction with trimethylsilyl isothiocyanate produced chlorothiocyanation adducts with a chlorine atom at the benzylic position. On the other hand, when 1 was treated with tetra-n-butylammonium iodide prior to the addition of alkenes, only iodoesterification occurred selectively. These mild reactions enable convenient site-selective difunctionalizations of substrates having two alkene moieties. NMR experiments suggested that the electrophilic reactive species in each reaction varied depending on the nature of the added nucleophile.
The vicinal functionalization of olefins: A facile route to the direct synthesis of β-chlorohydrins and β-chloroethers
Swamy, Peraka,Kumar, Macharla Arun,Reddy, Marri Mahender,Naresh, Mameda,Srujana, Kodumuri,Narender, Nama
, p. 26288 - 26294 (2014/07/08)
An efficient and environmentally benign protocol for the synthesis of vicinal chlorohydroxy and chloromethoxy derivatives in a highly regioselective manner from olefins using NH4Cl as a chlorine source and oxone as an oxidant in aqueous acetone and methanol is demonstrated. This methodology offers an additive and metal chloride free approach and is endowed with simple reaction conditions, high yields a broad substrate scope and good functional group tolerance. Moreover, the aromatic substrates with a terminal double bond exhibited merely Markovnikov selectivity, while the internal alkenes show exclusive regiocontrol and low to moderate diastereoselectivity.
Process for the preparation of optically active 2-halo-1-(substituted phenyl) ethanol
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, (2008/06/13)
The present invention provides an industrially advantageous process for the preparation of an optically active 2-halo-1-(substituted phenyl)ethanol useful as medicines, agricultural chemicals or as intermediates thereof; and a simple process for the prepa
