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Schuster, Gary B. Kim, Ji-In 2014-12-17T21:29:00Z 2014-12-17T21:29:00Z 10000-01-01 1992 1992 Part I. Enantioselective triplex Diels-Alder reaction. An investigation of the enantioselective triplex Diels-Alder reaction has been performed with optically active biaryl sensitizers, (-)1,1$\sp\prime$bis(2,4-dicyanonaphthalene) and (-)1,1$\sp\prime$bis(2,10-dicyanoanthracene). Irradiation of an optically active sensitizer in non-polar solvents containing substituted trans-$\beta$-methylstyrenes and cyclic dienes yielded endo (4+2) adducts with enantioselectivity up to 23%. Our report is the first observation of an enantioselective photochemical cycloaddition reaction which is catalyzed by a chiral sensitizer. The mechanistic investigation suggests the presence of diastereomeric exciplexes. The advantages and limitations of the reaction are discussed along with the results from the mechanistic study. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) Part II. Triplex Diels-Alder reaction with acetylenic dienophiles. An investigation of triplex Diels-Alder reaction has been carried out with sensitizers, 1,4-dicyanonaphthalene or 2,6,9,10-tetracyanoanthracene. Irradiation of a sensitizer in non-polar solvents containing acetylenic dienophiles and dienes yielded cycloaddition products. Results showed that either (4+2) or (2+2) cycloadducts are formed depending on whether the diene is cyclic or acyclic. Through product and photophysical studies, the scope and limitations of triplex Diels-Alder reaction with acetylenic dienophiles were examined. Made available in DSpace on 2014-12-17T21:29:00Z (GMT). No. of bitstreams: 1 9236501.pdf: 6191057 bytes, checksum: 5c9052a55dc246f278b1160595024546 (MD5) Previous issue date: 1992 Embargo set by: Seth Robbins for item 72436 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 130 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1992. http://hdl.handle.net/2142/72268 (UMI)AAI9236501 Chemistry, Organic The Triplex Diels-Alder Reaction: An Investigation of Enantioselectivity and Scope text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.