2-Alkoxyarenol-derived orthoquinols in carbon–oxygen, carbon–nitrogen and carbon–carbon bond-forming reactions
作者:Stéphane Quideau、Laurent Pouységu、Mayalen Oxoby、Matthew A Looney
DOI:10.1016/s0040-4020(00)00939-x
日期:2001.1
Silylated oxygen- and nitrogen-tethered orthoquinol acetates, generated by phenyliodine(III) diacetoxy-mediated oxidative acetoxylation of 2-alkoxyphenols in CH2Cl2 can be used to furnish regioselectively benzannulated heterocycles. Oxidative activation of 2-alkoxynaphthols with non-nucleophilic phenyliodine(III) bis(trifluoroacetoxy) in the presence of carbon nucleophiles, including oxidation sensitive silyl enol ethers, constitute a potentially valuable route to naturally occurring vicinally oxygenated benz[a]anthracene motifs. (C) 2000 Elsevier Science Ltd. All rights reserved.
Hypervalent iodine(III)-mediated oxidative acetoxylation of 2-methoxyphenols for regiocontrolled nitrogen benzannulation
作者:Stéphane Quideau、Laurent Pouységu、Anne-Virginie Avellan、Daniel K Whelligan、Matthew A Looney
DOI:10.1016/s0040-4039(01)01514-3
日期:2001.10
Nitrogen-tethered 2-methoxyphenols are conveniently dearomatized into synthetically useful orthoquinol acetates by treatment with phenyliodine(III) diacetate in methylene chloride at low temperature. Subsequent fluoride- or base-induce intramolecular nucleophilic addition reactions furnish indole and quinoline derivatives. The potential of this methodology for the synthesis or a functionalized lycorine-type alkaloid skeleton is introduced here. (C) 2001 Elsevier Science Ltd. All rights reserved.
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