Chemistry of oxa- and aza-bicyclic(4.1.0)heptenes, total synthesis of (+)-pancratistatin

Tian, Xinrong2014-03-142014-03-141995etd-06062008-163626http://hdl.handle.net/10919/38237Vinyloxiranes 6a-b and vinylaziridines 7a-b were prepared efficiently from halocyclohexadiene-cis-diols 1. Reactions of 6 and 7 with a variety of organometallic reagents were investigated in order to determine the stereo- and regiochemistry of ring opening with carbon nucleophiles. The results indicate that 6 and 7 could serve as useful new synthons for C-disaccharides and Amaryllidaceae alkaloid syntheses. The utility of synthon 7b has been demonstrated by a concise enantiocontrolled synthesis of (+)-pancratistatin (9). The key step involved the S<sub>N</sub>2 opening of 7b with the aryl cyanocuprate derived from amide 217 to generate the pivotal cyclization precursor.x, 156 leavesBTDapplication/pdfenIn CopyrightLD5655.V856 1995.T536Chemistry of oxa- and aza-bicyclic(4.1.0)heptenes, total synthesis of (+)-pancratistatinDissertationhttp://scholar.lib.vt.edu/theses/available/etd-06062008-163626/