53907-75-8Relevant articles and documents
STEREOCONTROL OF A TERTIARY HYDROXYL GROUP VIA MICROBIAL EPOXIDATION. A FACILE SYNTHESIS OF PROSTAGLANDIN ω-CHAINS
Takahashi, Osamu,Umezawa, Junko,Furuhashi, Keizo,Takagi, Motoyoshi
, p. 1583 - 1584 (1989)
Optically active 1,2-epoxy-2-methylalkanes(1), useful precursors of tertiary alcohols, were prepared by microbial oxidation and converted to prostaglandin ω-chains.
Asymmetric Hydrolysis of Epoxides using an Immobilized Enzyme Preparation from Rhodococcus sp.
Hechtberger, Petra,Wirnsberger, Gernot,Mischitz, Martin,Klempier, Norbert,Faber, Kurt
, p. 1161 - 1164 (1993)
An enzyme-catalyzed asymmetric hydrolysis of epoxides was achieved using an immobilized crude enzyme preparation derived from Rhodococcus sp. (NOVO SP 409).The mechanism of the reaction was shown to occur in a trans-specific hydrolytic opening via an SN2-type of reaction.Depending on the substitutional pattern of the substrate, optically active epoxides and 1,2-diols with varying optical purities were obtained (in one case e.e. 72percent).
Iron-Catalyzed Epoxidation of Linear α-Olefins with Hydrogen Peroxide
Mao, Shuxin,Budweg, Svenja,Spannenberg, Anke,Wen, Xiaodong,Yang, Yong,Li, Yong-Wang,Junge, Kathrin,Beller, Matthias
, (2022/01/26)
The combination of Fe(OTf)2 with N-methyl bis(picolylamine) (Me-bpa) L7 enables epoxidation of linear olefins including terminal, internal, and cyclic ones, using hydrogen peroxide as terminal oxidant under mild conditions. In the presence of picolinic acid as additive improved yields of epoxides up to 75 % have been achieved.
Remote Amino Acid Recognition Enables Effective Hydrogen Peroxide Activation at a Manganese Oxidation Catalyst
Costas, Miquel,Olivo, Giorgio,Vicens, Laia
supporting information, (2021/12/27)
Precise delivery of a proton plays a key role in O2 activation at iron oxygenases, enabling the crucial O?O cleavage step that generates the oxidizing high-valent metal–oxo species. Such a proton is delivered by acidic residues that may either
SYSTEMS AND METHODS FOR REGIOSELECTIVE CARBONYLATION OF 2,2-DISUBSTITUTED EPOXIDES
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Paragraph 0146; 0151; 0155, (2020/06/05)
Provided are methods of carbonylating cyclic substrates to produce carbonyl ated cyclic products. The cyclic substrates may be 2, 2-di substituted epoxides and the cyclic products may be β,β-di substituted lactones. The method may be carried out by forming and pressurizing a reaction mixture of the cyclic substrate, a solvent, carbon monoxide, and a [LA+][CO(CO)4-] catalyst, where [LA+] is a Lewis acid capable of coordinating to the cyclic substrate. The method may proceed with a regioselectivity of 90:10 or greater. The resulting carbonylated cyclic products may be converted to ketone aldol products that retain the stereochemistry and enantiomeric ratio of the carbonyl ated cyclic products.
Regioselective Carbonylation of 2,2-Disubstituted Epoxides: An Alternative Route to Ketone-Based Aldol Products
Hubbell, Aran K.,Lapointe, Anne M.,Lamb, Jessica R.,Coates, Geoffrey W.
supporting information, p. 2474 - 2480 (2019/02/14)
We report the regioselective carbonylation of 2,2-disubstituted epoxides to β,β-disubstituted β-lactones. Mechanistic studies revealed epoxide ring-opening as the turnover limiting step, an insight that facilitated the development of improved reaction conditions using weakly donating, ethereal solvents. A wide range of epoxides can be carbonylated to β-lactones, which are subsequently ring-opened to produce ketone-based aldol adducts, providing an alternative to the Mukaiyama aldol reaction. Enantiopure epoxides were demonstrated to undergo the carbonylation/ring-opening process with retention of stereochemistry to form enantiopure β-hydroxy esters.
Azidolysis of epoxides catalysed by the halohydrin dehalogenase from Arthrobacter sp. AD2 and a mutant with enhanced enantioselectivity: an (S)-selective HHDH
Mikleu?evi?, Ana,Primo?i?, Ines,Hrenar, Tomica,Salopek-Sondi, Branka,Tang, Lixia,Elenkov, Maja Majeri?
, p. 930 - 935 (2016/09/13)
Halohydrin dehalogenase from Arthrobacter sp. AD2 catalysed azidolysis of epoxides with high regioselectivity and low to moderate (S)-enantioselectivity (E?=?1–16). Mutation of the asparagine 178 to alanine (N178A) showed increased enantioselectivity towards styrene oxide derivatives and glycidyl ethers. Conversion of aromatic epoxides was catalysed by HheA-N178A with complete enantioselectivity, however the regioselectivity was reduced. As a result of the enzyme-catalysed reaction, enantiomerically pure (S)-β-azido alcohols and (R)-α-azido alcohols (ee???99%) were obtained.
METHODS FOR OBTAINING OPTICALLY ACTIVE EPOXIDES AND VICINAL DIOLS FROM 2,2-DISUBSTITUTED EPOXIDES
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Paragraph 0123, (2015/12/19)
The invention provides yeast strains, and polypeptides encoded by genes of such yeast strains, that have enantiospecific 2,2-disubstituted epoxide hydrolase activity. The invention also features nucleic acid molecules encoding such polypeptides, vectors c
Convenient and mild epoxidation of alkenes using heterogeneous cobalt oxide catalysts
Banerjee, Debasis,Jagadeesh, Rajenahally V.,Junge, Kathrin,Pohl, Marga-Martina,Radnik, Joerg,Brueckner, Angelika,Beller, Matthias
, p. 4359 - 4363 (2014/05/06)
A general epoxidation of aromatic and aliphatic olefins has been developed under mild conditions using heterogeneous CoxOy-N/C (x=1,3; y=1,4) catalysts and tert-butyl hydroperoxide as the terminal oxidant. Various stilbenes and aliph
Fe(PyTACN)-catalyzed cis-dihydroxylation of olefins with hydrogen peroxide
Prat, Irene,Font, David,Company, Anna,Junge, Kathrin,Ribas, Xavi,Beller, Matthias,Costas, Miquel
supporting information, p. 947 - 956 (2013/05/08)
A family of iron complexes with general formula [Fe(II)( R,Y,XPyTACN)(CF3SO3)2], where R,Y,XPyTACN=1-[2′-(4-Y-6-X-pyridyl)methyl]-4,7-dialkyl-1,4, 7-triazacyclononane, X and Y refer to the groups at positions 4 and 6 of the pyridine, respectively, and R refers to the alkyl substitution at N-4 and N-7 of the triazacyclononane ring, are shown to be catalysts for efficient and selective alkene oxidation (epoxidation and cis-dihydroxylation) employing hydrogen peroxide as oxidant. Complex [Fe(II)(Me,Me,HPyTACN)(CF 3SO3)2] (7), was identified as the most efficient and selective cis-dihydroxylation catalyst among the family. The high activity of 7 allows the oxidation of alkenes to proceed rapidly (30 min) at room temperature and under conditions where the olefin is not used in large amounts but instead is the limiting reagent. In the presence of 3 mol% of 7, 2 equiv. of H2O2 as oxidant and 15 equiv. of water, in acetonitrile solution, alkenes are cis-dihydroxylated reaching yields that might be interesting for synthetic purposes. Competition experiments show that 7 exhibits preferential selectivity towards the oxidation of cis olefins over the trans analogues, and also affords better yields and high [syn-diol]/[epoxide] ratios when cis olefins are oxidized. For aliphatic substrates, reaction yields attained with the present system compare favourably with state of the art Fe-catalyzed cis-dihydroxylation systems, and it can be regarded as an attractive complement to the iron and manganese systems described recently and which show optimum activity against electron-deficient and aromatic olefins. Copyright
