PREPARATION OF PYRIMIDINOPHANES FROM PYRIMIDINE-BASES

Treatment of pyrimidine bases such as uracil, thymine, and 5-fluoroura cil with X(CH2)(n)X (X = I or Br; n = 4-12) gave three types of pyrimi dinophanes. When the numbers of carbon atoms of X(CH2)(n)X are odd num bers (n = 5, 7, 9, 11), three structures of pyrimidinophanes could be differentiated on the basis of the C-13 NMR and mass spectra. Treatmen t of pyrimidinophanes with 1,4-naphthoquinone or maleimides in the pre sence of palladium(II) acetate gave the coupling products. Reaction of pyrimidinophanes with NaNO2 in the presence of palladium(II) acetate led to the nitration.