title: Synthesis of highly functionalized chiral nitriles by radical fragmentation of beta-hydroxy azides. Convenient transformation of aldononitriles into 1,4- and 1,5-iminoalditols.
abstract: The synthesis of highly functionalized nitriles by an alkoxyl radical fragmentation of cyclic beta-hydroxy azides is described. The alkoxyl radicals were generated by reaction of the alcohols with (diacetoxyiodo)benzene and iodine under mild conditions compatible with the presence of sensitive substituents and the protective groups most frequently used in carbohydrate chemistry. To explore the scope and limitations of this methodology, experiments were carried out using a variety of beta-hydroxy azides of the carbohydrate (1-6, 33, and 41), monoterpenoid (21 and 22), and steroid (23-25) families of natural products. Of special interest are the aldopentonitriles (15-18, 34, and 42) and aldotetrononitriles (19 and 20) synthesized from the corresponding 2-azido-2-deoxycarbohydrates. To demonstrate the versatility of these aldononitriles as chiral synthons, 1,4-imino-1-deoxysugar (37) and 1,5-imino-1-deoxysugar (43) analogues of the polyhydroxypyrrolidine and -piperidine types were prepared.
authors.affiliation: Instituto de Productos Naturales y Agrobiología del CSIC, Carretera de La Esperanza 3, 38206 La Laguna, Tenerife, Spain.
authors.forename: Rosendo
authors.initials: R
authors.lastname: Hernández
authors.forename: Elisa I
authors.initials: EI
authors.lastname: León
authors.forename: Pilar
authors.initials: P
authors.lastname: Moreno
authors.forename: Concepción
authors.initials: C
authors.lastname: Riesco-Fagundo
authors.forename: Ernesto
authors.initials: E
authors.lastname: Suárez
mesh_terms: D001386:Azides / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D008968:Molecular Conformation; D009570:Nitriles / Q000138:chemical synthesis* / Q000737:chemistry; D013402:Sugar Alcohols / Q000138:chemical synthesis*
chemical_list: D001386:Azides; D005609:Free Radicals; D009570:Nitriles; D013402:Sugar Alcohols