Rh(II) metallopeptides for asymmetric catalysis

dc.contributor.advisorBall, Zachary T.en_US
dc.contributor.advisorEngel, Paul S.en_US
dc.contributor.committeeMemberVerduzco, Rafaelen_US
dc.creatorSambasivan, Ramyaen_US
dc.date.accessioned2017-07-26T20:45:21Zen_US
dc.date.available2017-07-26T20:45:21Zen_US
dc.date.created2014-12en_US
dc.date.issued2015-02-17en_US
dc.date.submittedDecember 2014en_US
dc.date.updated2017-07-26T20:45:21Zen_US
dc.description.abstractThe development of peptides as chiral ligands for asymmetric Rh(II) catalysis is discussed in this work. Mother Nature’s solution to chiral ligand design is to make use of the naturally available chiral building blocks – amino acids. Polypeptides, built from amino acids, provide a diverse, modular and functional-group-rich framework for the development of selective transition- metal catalysts and enable facile ligand screening. The dirhodium core has a paddlewheel structure that can ligate readily to the side chain carboxylate of aspartate or glutamate in a peptide chain. When a peptide containing aspartates or glutamates in the i and i+4 position is complexed to dirhodium, the transition metal complex thus formed has a defined peptide secondary structure with retention of catalytic activity at the metal center. The first-generation approach used a solution-phase library of dirhodium bis-peptide catalysts for the enantioselective Si–H bond insertion and cyclopropanation. The parallel and anti-parallel orientation of bis-peptide catalysts was determined by pyrene fluorescence. Subsequently, parallel on-bead screening of catalyst libraries allowed significantly higher throughput by obviating the need for purification and isolation of individual catalysts. This enables the synthesis and screening of catalysts in 96-well plate format within a few days. More recently, a mono-peptide catalyst with a tridentate eq-eq-ax peptide ligand has been identified which exhibits differential behavior in solution and on bead. New insights into the development of immobilized homogeneous catalysts for stereoselective catalysis are discussed.en_US
dc.format.mimetypeapplication/pdfen_US
dc.identifier.citationSambasivan, Ramya. "Rh(II) metallopeptides for asymmetric catalysis." (2015) Diss., Rice University. <a href="https://hdl.handle.net/1911/95526">https://hdl.handle.net/1911/95526</a>.en_US
dc.identifier.urihttps://hdl.handle.net/1911/95526en_US
dc.language.isoengen_US
dc.rightsCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.en_US
dc.subjectmetallopeptideen_US
dc.subjectasymmetric catalysisen_US
dc.subjectrhodium catalysten_US
dc.titleRh(II) metallopeptides for asymmetric catalysisen_US
dc.typeThesisen_US
dc.type.materialTexten_US
thesis.degree.departmentChemistryen_US
thesis.degree.disciplineNatural Sciencesen_US
thesis.degree.grantorRice Universityen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophyen_US
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
SAMBASIVAN-DOCUMENT-2014.pdf
Size:
28.51 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 2 of 2
No Thumbnail Available
Name:
PROQUEST_LICENSE.txt
Size:
5.85 KB
Format:
Plain Text
Description:
No Thumbnail Available
Name:
LICENSE.txt
Size:
2.61 KB
Format:
Plain Text
Description: