Asymmetric Addition Reactions Catalyzed by Camphor-Derived Chiral β-Amino Alcohols and β-Amino Thiols
博士 === 國立清華大學 === 化學系 === 104 === 因申請專利緣故，資料延後公開 This thesis reports the application of camphor-derived chiral β-amino alcohols and β-amino thiols in asymmetric addition reactions. In the first part, a series of chiral amino alcohols 12a–l has been synthesized and used in the enantioselective ad...
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| Format: | Others |
| Language: | zh-TW |
| Published: |
2015
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| Online Access: | http://ndltd.ncl.edu.tw/handle/75m7z7 |
| Summary: | 博士 === 國立清華大學 === 化學系 === 104 === 因申請專利緣故，資料延後公開
This thesis reports the application of camphor-derived chiral β-amino alcohols and β-amino thiols in asymmetric addition reactions. In the first part, a series of chiral amino alcohols 12a–l has been synthesized and used in the enantioselective addition of dialkylzinc to aromatic aldimines. Application of the optimal chiral ligand 12a (10 mol%) with methanol (1.8 equiv.) as the additive to activate the reaction of aromatic aldimines with diethylzinc and dimethylzinc resulted in high yields (60–92%) and enantioselectivities (84–96% ee).
In the second part, a series of chiral amino alcohols 31e–42e, 43 and 44 has been synthesized and used in asymmetric Henry reaction. Application of the optimal chiral ligand 35e (2 mol%) with triethyl borate (2 equiv.) as the additive to activate the reaction of aldehyde with nitromethane and nitroethane resulted in yields (21–>99%) and enantioselectivities (82–96% ee). Notably, the addition of extra 34 mol% H2O could improve the adduct yield of para-chlorobenzaldehyde.
The third part reports the application of β-amino thiol 30 catalyzed asymmetric addition of ethyl diazoacetate to benzaldehyde to give β-hydroxy a-diazo ester in good yield (92%) and with moderate enantioselectivity (66% ee).
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