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Denmark, Scott E. Amburgey, Jack S. 2014-12-17T21:29:13Z 2014-12-17T21:29:13Z 10000-01-01 1994 1994 A new method for the highly stereoselective synthesis of trisubstituted olefins is presented. The method involves the stereoselective construction of various $\beta$-hydroxy phosphonamidates followed by their thermolysis to provide trisubstituted olefins in extremely high geometrical purity ($>$99/1). The stereoselective construction of $\beta$-hydroxy phosphonamidates could be accomplished through three main synthetic transformations. The first involves the acylation of various parent 1,3,2-oxazaphospholidines to provide monoalkylated $\beta$-keto phosphonamidates in good yield. The second step is the alkylation of the $\beta$-keto phosphonamidates to provide $\alpha,\alpha$-dialkylated $\beta$-keto phosphonamidates in high yield and very high diastereoselectivities. Finally, the highly diastereoselective reduction of the dialkylated $\beta$-keto phosphonamidates could be accomplished through the use of a variety of reducing agents to give $\beta$-hydroxy phosphonamidates in high yield and high diastereoselectivities. Thermolysis of the diastereomerically pure $\beta$-hydroxy phosphonamidates gave a variety of trisubstituted olefins in high yield and very high stereoselectivity. A discussion on anionic mediated olefinations as well as an extension into the stereoselective synthesis of tetrasubstituted olefins is also presented. Made available in DSpace on 2014-12-17T21:29:13Z (GMT). No. of bitstreams: 1 9503130.pdf: 9529588 bytes, checksum: eda802fe2c5b3f891f436a6e4575a1b1 (MD5) Previous issue date: 1994 Embargo set by: Seth Robbins for item 72462 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 263 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1994. http://hdl.handle.net/2142/72294 (UMI)AAI9503130 Chemistry, Organic Stereoselective Synthesis of Trisubstituted Olefins text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.