dc.contributor.author | Cheung, Didi Chiu Yee | |
dc.date.accessioned | 2012-04-30 13:39:07 (GMT) | |
dc.date.available | 2012-04-30 13:39:07 (GMT) | |
dc.date.issued | 2012-04-30T13:39:07Z | |
dc.date.submitted | 2012 | |
dc.identifier.uri | http://hdl.handle.net/10012/6670 | |
dc.description.abstract | Asymmetric conjugate addition is an important methodology for carbon-carbon bond formation in organic synthesis. While there is extensive literature on the asymmetric conjugate addition of a wide selection of donors to a variety of acceptors, there are relatively few reports on the asymmetric conjugate addition of heteroaryl groups. Almost all of these reports utilize catalytic amounts of both a rhodium compound and a chiral ligand, and usually employ organoboron reagents. Furthermore, these additions have been problematic due to protodeboronation. Other organocatalytic methods have offered low yields and moderate enantioselectivies.
The binaphthol / boronate catalyst system developed by the Chong group is effective in promoting asymmetric conjugate addition of 2-thienyl, 3-thienyl, 2-furyl, and 2-benzo[b]thienyl moieties to acyclic enones. The combination of 3,3ʹ-disubstituted binaphthols with diethyl heteroarylboronates generated 1,4-adducts with good yields and high enantioselectivities (up to 100% yield and 99.9:0.1 er). This catalyst system complements known methods of conjugate addition of heteroaryl groups involving transition metal catalysts and cyclic enone acceptors and is the most effective organocatalytic system reported to date. | en |
dc.language.iso | en | en |
dc.publisher | University of Waterloo | en |
dc.subject | binaphthols | en |
dc.subject | heteroarylboronates | en |
dc.title | Organocatalytic Asymmetric Conjugate Addition of Heteroaryl Moieties to α,β-Unsaturated Enones Using Boronates and 3,3ʹ-Disubstituted Binaphthols | en |
dc.type | Master Thesis | en |
dc.pending | false | en |
dc.subject.program | Chemistry | en |
uws-etd.degree.department | Chemistry | en |
uws-etd.degree | Master of Science | en |
uws.typeOfResource | Text | en |
uws.peerReviewStatus | Unreviewed | en |
uws.scholarLevel | Graduate | en |