58068-76-1Relevant academic research and scientific papers
Laccase/2,2,6,6-tetramethylpiperidinoxyl radical (TEMPO): An efficient catalytic system for selective oxidations of primary hydroxy and amino groups in aqueous and biphasic media
Díaz-Rodríguez, Alba,Martínez-Montero, Lía,Lavandera, Iván,Gotor, Vicente,Gotor-Fernández, Vicente
supporting information, p. 2321 - 2329 (2014/07/21)
Copper salts/2,2,6,6-tetramethylpiperidinoxyl radical (TEMPO) catalytic systems enable efficient aerobic oxidations of primary alcohols but they generally show a reduced reactivity in aqueous medium. Herein, we report an oxidative catalytic system composed of Trametes versicolor laccase and TEMPO, which is able to work in buffer solutions at room temperature using ambient air. Although this catalytic system displays great efficiency in aqueous systems, the addition of methyl tert-butyl ether allows the reduction of TEMPO loading, also enhancing the solubility of hydrophobic compounds. This practical methodology promotes the chemoselective aerobic oxidation of hydroxy or amino groups, leading to interesting organic derivatives such as aldehydes, lactones, hemiaminals or lactams.
Enantioselective preparation of δ-valerolactones with horse liver alcohol dehydrogenase
Diaz-Rodriguez, Alba,Iglesias-Fernandez, Javier,Rovira, Carme,Gotor-Fernandez, Vicente
, p. 977 - 980 (2014/05/06)
Horse liver alcohol dehydrogenase (HLADH) has been found to be a versatile biocatalyst for the desymmetrization of prochiral 3-arylpentane-1,5-diols, based on a two-step one-pot oxidation. This procedure has allowed the formation of valuable (S)-lactones in good to excellent conversions and enantiomeric excess. The catalytic performance of HLADH has been studied using several cofactor regeneration systems and cosolvents, finding great improvements in terms of activity with L-lactate dehydrogenase, while the stereoselectivity of the process was significantly improved when using tetrahydrofuran. Docking studies has revealed the pattern substitution importance in the selectivity and activity of this oxidative process. Not just horsing around: Horse liver alcohol dehydrogenase is found to be a versatile biocatalyst for the desymmetrization of 3-arylpentane-1,5-diols through a two-step one-pot oxidation. The catalytic performance of horse liver alcohol dehydrogenase (HLADH) is studied with several cofactor regeneration systems and cosolvents. Docking studies reveal the importance of pattern substitution in the selectivity and activity of this biotransformation.
The effect of pre-existing stereocenters in the intramolecular asymmetric Stetter reaction
Reynolds, Nathan T.,Rovis, Tomislav
, p. 6368 - 6378 (2007/10/03)
A series of disubstituted cyclopentanones have been synthesized by the intramolecular Stetter reaction. Racemic substrates containing one chiral center were used, allowing us the opportunity to observe a parallel kinetic resolution in the synthesis of 2,3- and 2,4-disubstituted cyclopentanones. The Stetter reaction of 2,5-disubstituted cyclopentanones proved to be substrate controlled, resulting in the selective formation of the cis-diasteromers with low ee.
Experimental studies of the anomeric effect. Part III. Rotameric preferences about the exo-cyclic c2-x bond in equatorial and axial 2-methoxy-and 2-methylamino-tetrahydropyrans
Booth, Harold,Dixon, J. Mark,Khedhair, Khedhair A.,Readshaw, Simon A.
, p. 1625 - 1652 (2007/10/02)
Values of3 J(CC), 3J(CH), 4J(CH) and 3J(HH), supported by n.O.enhancements, in nmr spectra of 2-methoxy- and 2-methyl-amino-tetrahydropyrans, point to a very strong preference for rotamers in which an exo-cyclic heteroatom lone pair is antiperiplanar to the endo-cyclic C2-O bond ("endo-anomeric effect").
