MARC Record from marc_columbia

LEADER: 03069cam a22003733i 4500
001 12198790
005 20180618183031.0
006 m o d
007 cr |n||||a||||
008 161005s2015 nyu|||| om 00| ||eng d
035 $a(OCoLC)962888778
035 $a(OCoLC)ocn962888778
035 $a(NNC)ACfeed:legacy_id:ac:200662
035 $a(NNC)ACfeed:doi:10.7916/D8JQ103Z
035 $a(NNC)12198790
040 $aNNC$beng$erda$cNNC
100 1 $aHu, Yue.
245 10 $aCatalyst Design for the Ionic Hydrogenation of C=N Bonds /$cYue Hu.
264 1 $a[New York, N.Y.?] :$b[publisher not identified],$c2015.
300 $a1 online resource.
336 $atext$btxt$2rdacontent
337 $acomputer$bc$2rdamedia
338 $aonline resource$bcr$2rdacarrier
502 $aThesis (Ph.D.)--Columbia University, 2015.
500 $aDepartment: Chemistry.
500 $aThesis advisor: Jack R. Norton.
520 $aNew chiral half-sandwich Ru hydride enantiomers with asymmetric disubstitution on the Cp ligand have been successfully synthesized and resolved. An enantiopure thiolate ligand was installed on the Ru center to form a pair of diastereomers, which were separated by crystallization via vapor diffusion of pentane into their saturated Et2O solution. Racemization occurred at elevated temperatures, but a room temperature conversion pathway was developed to remove the chiral thiolate ligand and generate the enantiopure hydride complex. Two new Rh(III) hydride complexes and their Ir analogues have been synthesized and characterized. The hydride complexes readily transfer H– to the N-carbophenoxypyridinium cation at room temperature, giving mixtures of 1,2- and 1,4-dihydropyridine products. In CD3CN, all four hydrides give nearly the same product ratio, demonstrating that the hydride transfer mechanism is outer sphere. In weak or non-coordinating solvents, the resulting 16-electron cations catalyze the isomerization of 1,2- to 1,4-dihydropyridine at rates that depend upon the cation and the solvent.
520 $aThe fastest isomerization was observed with the Rh(III) cation [Cp*Rh(2-(2-pyridyl)phenyl)]+, Acetonitrile can trap the 16-electron cations resulting from hydride transfer, dramatically slowing the isomerization process. The thermodynamics and kinetics of hydride, hydrogen atom and proton transfer reactions of the Rh(III) hydride, Cp*Rh(2-(2-pyridyl)phenyl)H, were studied both thermodynamically and kinetically. This hydride is both a good hydride and hydrogen atom donor, but a poor proton donor. This previously unobserved combination of properties is due to the high energy of the hydride’s conjugate base, [Cp*Rh(2-(2-pyridyl)phenyl)]−. Its exceptional hydride donor ability makes Cp*Rh(2-(2-pyridyl)phenyl)H a very efficient catalyst for the ionic hydrogenation of iminium cations.
653 0 $aTransition metal hydrides
653 0 $aCatalysts
653 0 $aHydrogenation
653 0 $aChemistry
856 40 $uhttps://doi.org/10.7916/D8JQ103Z$zClick for full text
852 8 $blweb$hDISSERTATIONS