SYNTHESIS AND PROPERTIES OF SUBSTITUTED 10-PHENYL-10-HYDROXY-1OH-PYRIDOCHROMENES

Article abstract of DOI:10.1007/BF00506153

It is shown that 2-aryloxy-3-benzoyl-6-methylpyridines undergo cyclization to the corresponding derivatives of 10-phenyl-10-hydroxy-10H-pyrido<2,3-b>chromenes under the influence of concentrated sulfuric acid in glacial acetic acid.The pK_R+ values of the products, which range from -6.28 to -9.27 and correlate with the ?_p⁰ and ?_R⁰ meta substituent constants, depending on the position of the substituent, were determined by spectrophotometry.