83-33-0Relevant articles and documents
Photoinduced Double Addition of Acetylene to 3-Oxocyclopent-1-ene-1-carbonitrile or 3-Oxocyclopent-1-enyl Acetate Leading to 2,3-Dihydro-1H-inden-1-one and Other Rearranged Products
Cavazza, Marino,Guella, Graziano,Pietra, Francesco
, p. 1608 - 1615 (1988)
UV Irradiation of 3-oxocyclopent-1-enyl acetate (17) and acetylene in MeCN at 0 deg C gives, besides the product of normal enone-alkyne cycloaddition (cis-4-oxobicyclohept-6-en-1-yl acetate, 18) and its product of oxa-di-?-methane rearrangement (5-oxotricyclo2,7>hept-2-yl acetate, 19), unexpected products of further addition of a molar equivalent of acetylene.These are indanone (= 2,3-dihydro-1H-inden-1-one, 16), in 21percent yield, cis-1-cisoid-1,2-cis-2- (20) and cis-1-transoid-1,2-cis-2,7-oxotricyclo2,5>non-3-en-1-yl acetate (21), 4-oxo-7-'exo'-vinyltricyclo2,6>hept-2-yl acetate (22), cis-4-oxo-6 -'endo'- (23) and cis-4-oxo-6-'exo'-vinylbicyclohept-1-yl acetate (24), and cis-4-oxo-7-'exo'-vinylbicyclohept-1-yl acetate (25).At least in part, indanone must be formed via intermediates 20 and 21.In fact, on heating a 9:1 mixture 20/21, indanone is obtained quantitatively.With 3-oxocyclopent-1-ene-1-carbonitrile (15) in place of 17, indanone is formed in lower (8percent) yield besides much tars.
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Price,Lewis
, p. 2553 (1939)
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Luh et al.
, p. 641 (1979)
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Covalent Linkage of an R-ω-Transaminase to a d-Amino Acid Oxidase through Protein Splicing to Enhance Enzymatic Catalysis of Transamination
Du, Kun,Li, Rong,Zhang, Dongrui,Feng, Wei
, p. 701 - 709 (2019)
R-ω-Transaminases (RTAs) catalyse the conversion of R-configured amines [e.g., (R)-1-phenylethylamine] into the corresponding ketones (e.g., acetophenone), by transferring an amino group from an amino donor [e.g., (R)-1-phenylethylamine] onto an amino acceptor (e.g., pyruvate), resulting in a co-product (e.g., d-alanine). d-Alanine can be deaminated back to pyruvate by d-amino acid oxidase (DAAOs). Here, through in vivo subunit splicing, the N terminus of an RTA subunit (RTAS) was specifically ligated to the C terminus of a DAAO subunit (DAAOS) through native peptide bonds (RTA&DAAO). RTAS is in close proximity to DAAOS, at a molecular-scale distance. Thus the transfer of pyruvate and d-alanine between RTA and DAAO can be directional and efficient. Pyruvate→d-alanine→pyruvate cycles are efficiently formed, thus promoting the forward transamination reaction. In a different, in vitro noncovalent approach, based on coiled-coil association, the RTAS N terminus was specifically associated with the DAAOS C terminus (RTA#DAAO). In addition, the two mixed individual enzymes (RTA+DAAO) were also studied. RTA&DAAO has a shorter distance between the paired subunits (RTAS–DAAOS) than RTA#DAAO, and the number of the paired subunits is higher than in the case of RTA#DAAO, whereas RTA+DAAO cannot form the paired subunits. RTA&DAAO exhibited a transamination catalysis efficiency higher than that of RTA#DAAO and much higher than that of RTA+DAAO.
Improved synthetic route to methyl 1-fluoroindan-1-carboxylate (FICA Me ester) and 4-methyl derivatives
Koyanagi, Jyunichi,Kamei, Tomoyo,Ishizaki, Miyuki,Nakamura, Hiroshi,Takahashi, Tamiko
, p. 816 - 819 (2014)
An improved synthetic route has been developed for the preparation of methyl 1-fluoroindan-1-carboxylate (FICA Me ester) from 1-indanone. Methyl 4-methyl-1-fluoroindan-1-carboxylate (4-Me-FICA Me ester) was also prepared following the same procedure.
Rational Construction of an Artificial Binuclear Copper Monooxygenase in a Metal-Organic Framework
Feng, Xuanyu,Song, Yang,Chen, Justin S.,Xu, Ziwan,Dunn, Soren J.,Lin, Wenbin
supporting information, p. 1107 - 1118 (2021/01/25)
Artificial enzymatic systems are extensively studied to mimic the structures and functions of their natural counterparts. However, there remains a significant gap between structural modeling and catalytic activity in these artificial systems. Herein we report a novel strategy for the construction of an artificial binuclear copper monooxygenase starting from a Ti metal-organic framework (MOF). The deprotonation of the hydroxide groups on the secondary building units (SBUs) of MIL-125(Ti) (MIL = Matériaux de l'Institut Lavoisier) allows for the metalation of the SBUs with closely spaced CuI pairs, which are oxidized by molecular O2 to afford the CuII2(μ2-OH)2 cofactor in the MOF-based artificial binuclear monooxygenase Ti8-Cu2. An artificial mononuclear Cu monooxygenase Ti8-Cu1 was also prepared for comparison. The MOF-based monooxygenases were characterized by a combination of thermogravimetric analysis, inductively coupled plasma-mass spectrometry, X-ray absorption spectroscopy, Fourier-transform infrared spectroscopy, and UV-vis spectroscopy. In the presence of coreductants, Ti8-Cu2 exhibited outstanding catalytic activity toward a wide range of monooxygenation processes, including epoxidation, hydroxylation, Baeyer-Villiger oxidation, and sulfoxidation, with turnover numbers of up to 3450. Ti8-Cu2 showed a turnover frequency at least 17 times higher than that of Ti8-Cu1. Density functional theory calculations revealed O2 activation as the rate-limiting step in the monooxygenation processes. Computational studies further showed that the Cu2 sites in Ti8-Cu2 cooperatively stabilized the Cu-O2 adduct for O-O bond cleavage with 6.6 kcal/mol smaller free energy increase than that of the mononuclear Cu sites in Ti8-Cu1, accounting for the significantly higher catalytic activity of Ti8-Cu2 over Ti8-Cu1.
Organotellurium-catalyzed oxidative deoximation reactions using visible-light as the precise driving energy
Deng, Xin,Qian, Rongrong,Zhou, Hongwei,Yu, Lei
supporting information, p. 1029 - 1032 (2020/10/23)
Irradiated by visible light, the recyclable (PhTe)2-catalyzed oxidative deoximation reaction could occur under mild conditions. In comparison with the thermo reaction, the method employed reduced catalyst loading (1 mol% vs. 2.5 mol%), but afforded elevated product yields with expanded substrate scope. This work demonstrated that for the organotellurium-catalyzed reactions, visible light might be an even more precise driving energy than heating because it could break the Te–Te bond accurately to generate the active free radical catalytic intermediates without damaging the fragile substituents (e.g., heterocycles) of substrates. The use of O2 instead of explosive H2O2 as oxidant affords safer reaction conditions from the large-scale application viewpoint.