Electrophilic cyclization of 3-alkynyl-4-chalcogen-2-H-chromenes: synthesis of 3-halo-chalcogenophene[3,2-c]chromene derivatives
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چکیده
منابع مشابه
K2CO3-mediated synthesis of functionalised 4-substituted-2-amino-3-cyano-4H-chromenes via Michael-cyclization reactions.
An efficient approach for the synthesis of functionalized 4-substituted-2-amino-3-cyano-4H-chromenes moderate to high yields (up to 98%) has been achieved via a tandem K2CO3 catalyzed conjugate addition-cyclization reaction of malononitrile and a range of Knoevenagel adducts previously formed from oxindole, pyrazolone, nitromethane, N,N-dimethylbarbituric acid or indanedione. This methodology d...
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ژورنال
عنوان ژورنال: Tetrahedron Letters
سال: 2011
ISSN: 0040-4039
DOI: 10.1016/j.tetlet.2010.11.049