Organocatalytic conjugate addition of nitroalkanes to 2H-chromene-3-carbaldehydes: synthesis of highly functionalized chroman derivatives
نویسندگان
چکیده
منابع مشابه
Enantioselective cascade double Michael addition of 3-nitro-2H-chromenes and acyclic enones: efficient synthesis of functionalized tricyclic chroman derivatives.
An efficient protocol for the asymmetric construction of enantiomerically enriched tetrahydro-6H-benzo[c]chromenes and their derivatives has been developed. The corresponding products were obtained by the cascade double Michael addition of 3-nitro-2H-chromenes and their derivatives with α,β-unsaturated ketones catalyzed by a combination of a quinine-derived primary amine and benzoic acid. Throu...
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We report a novel Lewis acid catalysed tandem reaction of isocyanides, chromone 3-carboxylic acid and nucleophiles. An experimentally very simple procedure, involving the use of microwave irradiation in the presence of a Lewis acid catalyst, affords a representative collection of chromone-2-carboxamides and chromone-2-carboxamido-3-esters in high yields, in just a few minutes. Such an unprecede...
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ژورنال
عنوان ژورنال: Arkivoc
سال: 2010
ISSN: 1551-7012
DOI: 10.3998/ark.5550190.0010.e30