| Summary: | 碩士 === 國立東華大學 === 化學系 === 99 === This thesis describes the synthesis and application of pinene-based bipyridine ligands 1, 2, 3 and 15. These ligands were applied to various asymmetric reactions including Nozaki-Hiyama-Kishi allylation, Henry reaction, alkynylation of aldehydes and epoxide ring opening reaction. Unfortunately, asymmetric reactions did not exhibit good enantioselectivity.
Interestingly, during an asymmetric addition of phenylacetylene to aldehyde using ligand 3 was found ethylated product as a side product with enriched ee (69% ee). When ligand 3 was applied for diethylzinc addition reaction, gratifyingly, very higher range of enantioselectivities (up to 97% ee) and yields (up to 99%) were achieved for various aldehydes. The optimum conditions 10 mol% 3, diethylzinc (2 eq), in toluene at 20 ºC for 57 hours, were used for 2-naphthal to give the correspond by alcohol up to 97% ee.
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