Aldol reactions are widely used in forming new carbon-carbon bonds. Since the discovery of the aldol condensation, controlling the relative and absolute stereochemistry in aldol chemistry has been a major interest in organic chemistry. Efforts in achieving diastereoselectivity in aldol reactions via chelation of Lewis acids to chiral aldehydes are reviewed. The following chapters discuss the diastereoselectivities of hydrogen-mediated reductive aldol reactions. Herein, a highly diastereoselective reductive aldol coupling reactions with broad substrate scope using rhodium catalysts ligated to (2-furyl)₃P were studied. It was demonstrated that the coupling of enones with alpha-amino aldehydes proceeds with high diastereoselectivity via chelation control. The second topic deals with phosphine-mediated furan ring formation. Derivatives of furan are often found in natural products and therapeutic agents. To provide a more facile route to substituted furans, we have developed a phosphine mediated reductive cyclization of gamma-acyloxy butynoates. In this reaction, phosphine is involved in both the reductive formation of allenyl ketones from acyloxy butynoates and the subsequent catalytic cyclization. / text
Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/29613 |
Date | 27 April 2015 |
Creators | Jung, Cheol-Kyu |
Source Sets | University of Texas |
Language | English |
Detected Language | English |
Type | Thesis |
Format | electronic |
Rights | Copyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works. |
Page generated in 0.0096 seconds