The reaction of 3-cyanochromones with N-and C-nucleophiles begins with an attack at C-2 atom with subsequent opening of the γ-pyrone ring and recyclization at the C= O or C≡ N groups [1-3]. Nucleophilic 1, 2-addition at the cyano group usually does not occur [1], while the reactions with aromatic amines [4] and methylenetriphenylphosphorane (Ph3P= CH2)[5] terminate at the stage of open products 1 and 2. Since the assumption of a number of ...
