title: The efficient synthesis of morphinandienone alkaloids by using a combination of hypervalent iodine(III) reagent and heteropoly acid.
abstract: The non-phenolic coupling reaction of benzyltetrahydroisoquinolines (laudanosine derivatives) by using a hypervalent iodine(III) reagent is described. In general, chemical oxidation of laudanosine gives glaucine. In contrast to general chemical oxidizing reagent systems, the novel use of reagent combination of phenyliodine bis(trifluoroacetate) (PIFA), and heteropoly acid (HPA) afforded morphinandienone alkaloids in excellent yields. In order to achieve the coupling reaction with simple reaction procedure, the use of HPA supported on silica gel instead of HPA was demonstrated and sufficient yield was exerted again. The present reagent system, PIFA/HPA, was also applied to the oxidation of other non-phenolic benzyltetrahydroisoquinolines and the high yield conversion to morphinandienones was accomplished.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Hamamoto
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Shiozaki
authors.forename: Hisanori
authors.initials: H
authors.lastname: Nambu
authors.forename: Kayoko
authors.initials: K
authors.lastname: Hata
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tohma
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kita
mesh_terms: D000143:Acids / Q000737:chemistry*; D000470:Alkaloids / Q000737:chemistry*; D007455:Iodine / Q000737:chemistry*; D007546:Isoquinolines / Q000737:chemistry; D015394:Molecular Structure; D009019:Morphinans / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D000143:Acids; D000470:Alkaloids; D007546:Isoquinolines; D009019:Morphinans; C495883:morphinandienone; D007455:Iodine