Preparation of tetrahydrofuran, γ-lactone, chromanol and pyrrolidine systems by sequential 5-exo-digonal radical cyclization, 1,5-hydrogen transfer from silicon, and 5-endo-trigonal cyclization
摘要:
Sequential 5-exo-digonal radical closure, intramolecular 1,5-hydrogen transfer from silicon to carbon, and 5-endo-trigonal closure of the resulting silicon-centred radicals are used to make five- and six-membered heterocycles containing oxygen or nitrogen.
Preparation of tetrahydrofuran, γ-lactone, chromanol and pyrrolidine systems by sequential 5-exo-digonal radical cyclization, 1,5-hydrogen transfer from silicon, and 5-endo-trigonal cyclization
摘要:
Sequential 5-exo-digonal radical closure, intramolecular 1,5-hydrogen transfer from silicon to carbon, and 5-endo-trigonal closure of the resulting silicon-centred radicals are used to make five- and six-membered heterocycles containing oxygen or nitrogen.
Systematic Construction of a Monotetrahydrofuran-Ring Library inAnnonaceous Acetogenins by Asymmetric Alkynylation and Stereodivergent Tetrahydrofuran-Ring Formation
diastereoisomers of the monotetrahydrofuran-ring cores of annonaceousacetogenins have been synthesized through utilization of asymmetric alkynylation and stereodivergent one-pot tetrahydrofuran-ring formation. In all cases, the asymmetric alkynylation proceeded with very high diastereoselectivity to give eight kinds of optically pure tetrahydrofuran core from a common alpha-oxyaldehyde. We also describe