Iodine(III)-mediated generation of nitrogen-tethered orthoquinol acetates for the construction of oxygenated indole, quinoline, and phenanthridine alkaloid motifs.
Functionalized indole and quinoline derivatives are conveniently prepared from nitrogen-tethered 2-methoxyphenols via phenyliodine(III) diacetate mediated oxidative acetoxylation, followed by a fluoride- or base-induced intramolecular nucleophilic addition reaction. This regioselective Michael-type addition step is further discussed in view of the rearrangement of orthoquinol acetate intermediates into paraquinol acetates that is sometimes observed in situ. Application of this methodology to the synthesis of a functionalized phenanthridine, and its potential for the construction of polyoxygenated lycorine-type alkaloid skeleta are here described.
Pouységu
Laurent
L
Laboratoire de Chimie des Substances Végétales, Centre de Recherche en Chimie Moléculaire, Université Bordeaux 1, 351 cours de la Libération, 33405 Talence Cedex, France.
Avellan
Anne-Virginie
AV
Quideau
Stéphane
S
D000085:Acetates / Q000737:chemistry*; D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D006873:Hydroquinones / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis*; D007455:Iodine / Q000737:chemistry*; D015394:Molecular Structure; D017672:Nitrogen Compounds / Q000138:chemical synthesis*; D011804:Quinolines / Q000138:chemical synthesis*; D013696:Temperature
D000085:Acetates; D000470:Alkaloids; D006873:Hydroquinones; D007211:Indoles; D017672:Nitrogen Compounds; D011804:Quinolines; D007455:Iodine