14447-34-8Relevant articles and documents
An improved synthesis of a polymer-supported distannane and its application to radical formation
Junggebauer, Joerg,Neumann, Wilhelm P.
, p. 1301 - 1310 (1997)
A polymer-supported distannane 1 was prepared by treatment of tin halide resin with lithium naphthalenide or sodium naphthalenide in THF. The content of the polymers 1 was determined to be 0.95 to 1.13 mmol/g tin as ditin. The polymer-supported distannane reagent was successfully applied to radical cyclizations of acyclic α-haloesters to yield γ-butyrolactones.
SUPRAphos-based palladium catalysts for the kinetic resolution of racemic cyclohexenyl acetate
Jiang, Xiao-Bin,Van Leeuwen, Piet W. N. M.,Reek, Joost N. H.
, p. 2287 - 2289 (2007)
High-throughput screening of the SUPRAphos library revealed a palladium catalyst based on supramolecular ligands that gave fast and highly efficient kinetic resolution of cyclohexenyl acetate with an S-value up to 12. The Royal Society of Chemistry.
PALLADIUM-CATALYZED ASYMMETRIC COUPLING REACTIONS BETWEEN ALLYLIC ACETATES AND ORGANOZINC REAGENTS. MECHANISTIC IMPLICATIONS
Fiaud, Jean-Claude,Aribi-Zouioueche, Louisa
, p. 383 - 388 (1985)
Asymmetric induction and deuterium distribution studies have provided information about the mechanism of the palladium-catalyzed coupling reaction between allylic acetates and phenylzinc chloride, namely the presence of a symmetric η3-allylic ligand in the inetrmediate, probably along with a monodentate phosphine ligand.
A catalytic system for allylic acetoxylation consisting of palladium (II) and nitrate and using oxygen as final oxidant
Magnus Larsson,Akermark, Bjoern
, p. 2523 - 2526 (1993)
Cyclohexane is oxidized to cyclohexenyl acetate in 92% yield by 5 mol% palladium acetate and 5 mol% iron (III) nitrate in acetic acid under an atmosphere of oxygen. Addition of chloride or acetate are negative for the yield while addition of acetic anhydr
Carbon-13 pulse Fourier transform NMR. Conformational preference of the hydroxyl and the acetoxyl group in 2-cyclohexenol and its acetate
Senda,Imaizumi
, p. 3813 - 3815 (1974)
13C Fourier transform NMR spectra of cis and trans 5-t-butyl-2-cyclohexenols, 2-cyclohexenol and their acetates have been examined indicating that the pseudo-axial orientation of the hydroxyl and the acetoxyl group at the allylic position is fa
Palladium-catalyzed deracemization of allylic carbonates in water with formation of allylic alcohols: Hydrogen carbonate ion as nucleophile in the palladium-catalyzed allylic substitution and kinetic resolution
Luessem, Bernhard J.,Gais, Hans-Joachim
, p. 6066 - 6067 (2003)
The palladium-catalyzed deracemization of racemic cyclic and acyclic allylic methyl carbonates in water in the presence of N,N′-(1R,2R)-1,2-cyclohexanediylbis[2-(diphenylphophino)benzamide] proceeds with high enantioselectivities to give the corresponding allylic alcohols in high yields. This deracemization involves a palladium-catalyzed allylic substitution with the in-situ-formed hydrogen carbonate ion and an irreversible decomposition of the intermediate allylic hydrogen carbonates, with formation of the corresponding allylic alcohols. The palladium-catalyzed reaction of racemic cyclic allylic acetates with potassium hydrogen carbonate in water in the presence of the chiral bisphosphane proceeds with a highly selective kinetic resolution to give the corresponding allylic alcohols and allylic acetates. Copyright
A further step to sustainable palladium catalyzed oxidation: Allylic oxidation of alkenes in green solvents
dos Santos Costa, Maíra,de Camargo Faria, Amanda,Mota, Rayssa L.V.,Gusevskaya, Elena V.
, (2021/09/14)
The palladium catalyzed oxidation of alkenes with molecular oxygen is a synthetically important reaction which employs palladium catalysts in solution; therefore, a solvent plays a critical role for the process. In this study, we have tested several green solvents as a reaction medium for the allylic oxidation of a series of alkenes. Dimethylcarbonate, methyl isobutyl ketone, and propylene carbonate, solvents with impressive sustainability ranks and very scarcely exploited in palladium catalyzed oxidations, were proved to be excellent alternatives for the solvents conventionally employed in these processes, such as acetic acid. Palladium acetate alone or in the combination with p-benzoquinone efficiently operates as the catalyst for the oxidation of alkenes by dioxygen under 5–10 atm. For most substrates, the systems in green solvents showed better selectivity for allylic oxidation products as compared to pure acetic acid; moreover, the reactions in propylene carbonate solutions occurred even faster than in acetic acid.
Discovery and Design of Family VIII Carboxylesterases as Highly Efficient Acyltransferases
Müller, Henrik,Godehard, Simon P.,Palm, Gottfried J.,Berndt, Leona,Badenhorst, Christoffel P. S.,Becker, Ann-Kristin,Lammers, Michael,Bornscheuer, Uwe T.
supporting information, p. 2013 - 2017 (2020/11/30)
Promiscuous acyltransferase activity is the ability of certain hydrolases to preferentially catalyze acyl transfer over hydrolysis, even in bulk water. However, poor enantioselectivity, low transfer efficiency, significant product hydrolysis, and limited substrate scope represent considerable drawbacks for their application. By activity-based screening of several hydrolases, we identified the family VIII carboxylesterase, EstCE1, as an unprecedentedly efficient acyltransferase. EstCE1 catalyzes the irreversible amidation and carbamoylation of amines in water, which enabled the synthesis of the drug moclobemide from methyl 4-chlorobenzoate and 4-(2-aminoethyl)morpholine (ca. 20 % conversion). We solved the crystal structure of EstCE1 and detailed structure–function analysis revealed a three-amino acid motif important for promiscuous acyltransferase activity. Introducing this motif into an esterase without acetyltransferase activity transformed a “hydrolase” into an “acyltransferase”.
Carbamate-based P,O-ligands for asymmetric allylic alkylations
Pálv?lgyi, ádám Márk,Schnürch, Michael,Bica-Schr?der, Katharina
, (2020/05/18)
Herein we report the design and successful catalytic application of modified Trost-ligands in asymmetric allylic alkylation (AAA) reactions. A small set of carbamate-monophosphine P,O-ligands has been prepared in a straightforward two-step synthetic procedure. After optimization of the reaction conditions, high catalytic activities and excellent enantioselectivity up to >99% have been attained.
CHOLINE METABOLISM INHIBITORS
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Page/Page column 50; 102-103, (2020/07/05)
The present disclosure relates to compounds, compositions and methods for inhibiting choline metabolism, e.g., conversion of choline to trimethylamine. Disclosed herein are compounds, compositions, and methods for inhibiting choline metabolism, e.g., conversion of choline to TMA. Also disclosed herein are compounds, methods and compositions for inhibiting choline metabolism by gut microbiota resulting in reduction in the formation of trimethylamine (TMA) and trimethylamine N-oxide (TMAO).
