1989-33-9Relevant articles and documents
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Liebermann,Zsuffa
, p. 206 (1911)
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Fixation of Carbon Dioxide with Diphenylcarbodiimide as a Model of Biotin Enzyme Active Site and a Weak Base: The Carboxylation of Fluorene under Mild Conditions
Chiba, Koji,Tagaya, Hideyuki,Karasu, Masa,Ono, Tsuyoyuki,Saito, Masaru,Ashikagaya, Atsushi
, p. 3738 - 3740 (1991)
Carbon dioxide was directly fixed into fluorene in the presence of diphenylcarbodiimide (DPC) as a model of a biotin enzyme active site and potassium hydrogencarbonate.It was considered that not only carbon dioxide but also the hydrogencarbonate ion were the carbon source in the presence of DPC.Weak bases such as potassium acetate, potassium propionate, and potassium formate were also effective for carboxylation.
Kawabata et al.
, p. 2822 (1974)
Flash photolysis of 10-diazo-9(10H)-phenanthrenone in aqueous solution. Hydration of fluorenylideneketene and the fluorene-9-carboxylic acid keto-enol system
Andraos,Chiang,Kresge,Popik
, p. 8417 - 8424 (1997)
Flash photolysis of 10-diazo-9(10H)-phenanthrenone in aqueous solution was found to give two successively formed transient species and to produce fluorene-9-carboxylic acid as the major reaction product. These transients were identified, through solvent isotope effects and the form of acid-base catalysis, as fluorenylideneketene, formed by photo-Wolff reaction of the diazophenanthrenone, and fluorene-9-carboxylic acid enol, formed by hydration of this ketene. Analysis of the rate profile of the enol ketonization reaction produced the first and second ionization constants for the enol ionizing as an oxygen acid, pQ(a)(E) = 2.01 and pQ'(a)(E) = 9.61, respectively. The rate of enolization of fluorene-9-carboxylic acid was also determined, by bromine scavenging, and that, coupled with a literature value of the acidity constant of this acid, allowed evaluation of the two keto-enol equilibrium constants (pK(E) = 9.67 for interconverting un-ionized carboxylic acid and enol and pK'(E) = 8.24 for interconverting singly ionized acid and enol), and it also allowed evaluation of the two carbon acid acidity constants (pQ(a)(K) = 11.67 for ionization of the un-ionized carboxylic acid as a carbon acid and pQ'(a)(K) = 17.85 for ionization of its carboxylate ion as a carbon acid). (All acidity constants are concentration quotients applicable at ionic strength 0.10 M.) These keto-enol equilibrium constants and acid dissociation constants are large because of the enol and enolate ion stabilizing effects of the cyclopentadienyl ring of the fluorenyl group; this ring also makes fluorenylideneketene an unusually reactive substance.
Electrogenerated Sm(II)-Catalyzed CO2 Activation for Carboxylation of Benzyl Halides
Bazzi, Sakna,Schulz, Emmanuelle,Mellah, Mohamed
supporting information, p. 10033 - 10037 (2019/12/24)
Sm(II)-catalyzed carboxylation of benzyl halides is reported through the electrochemical reduction of CO2. The transformation proceeds under mild reaction conditions to afford the corresponding phenylacetic acids in good to excellent yields. This user-friendly and operationally simple protocol represents an alternative to traditional strategies, which usually proceeds through the C(sp3)-halide activation pathway.
CATALYST COMPONENT FOR OLEFIN POLYMERIZATION AND APPLICATION THEREOF
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Paragraph 0096, (2017/10/17)
Provided is a solid catalyst component for olefin polymerization, which comprises Mg, Ti, a halogen and an electron donor. The electron donor is selected from at least one of ring-substituted ether-acid ester compounds of the general formula (I). Also provided are a catalyst containing the solid catalyst component and the application of the catalyst in reactions of olefin polymerization, particularly in the reaction of propylene polymerization.
Ni-catalyzed direct carboxylation of benzyl halides with CO2
León, Thierry,Correa, Arkaitz,Martin, Ruben
supporting information, p. 1221 - 1224 (2013/03/14)
A novel Ni-catalyzed carboxylation of benzyl halides with CO2 has been developed. The described carboxylation reaction proceeds under mild conditions (atmospheric CO2 pressure) at room temperature. Unlike other routes for similar means, our method does not require well-defined and sensitive organometallic reagents and thus is a user-friendly and operationally simple protocol for assembling phenylacetic acids.
