Tandem Allylic Isomerization – IMDAF Reactions and Other Isomerizations

The first section of this thesis describes a novel allylic isomerization, followed by an intra-molecular Diels-Alder furan cycloaddition, fragmentation, aromatization, and N-Boc deprotection cascade that leads to the formation of synthetically and biologically useful 5,6,7-substituted indoles. Various 5,6,7-substituted indoles are synthesized in moderate to good yield using this convergent method. Nonthermal microwave effects also prove to be essential in this transformation. The second section describes the extension of our indole synthesis methodology through a microwave assisted intramolecular Diels-Alder furan cycloaddition to a 5-hydroxyindole synthesis from readily available alkynals and alkynones. This convergent procedure is compatible with multiple-functionalities in the 4-position of the indole, including electron-withdrawing and electron-donating groups. Yields range from 44 to 64%. The third section describes a methodology study of the alkyne isomerization reaction using a non-nucleophilic base. After screening of reaction conditions, optimal conditions were achieved by the use of 2.2 equiv of LiTMP in THF (1.0 M substrate concentration) at r.t. for 1 h