A NEW GENERAL-SYNTHESIS OF POLYCYCLIC AROMATIC-COMPOUNDS BASED ON ENAMINE CHEMISTRY

Alkylation of enamines and enamine salts by benzylic and (beta-haloethyl)aryl halides, respectively, followed by acidic cyclodehydration and dehydrogenation provides an efficient synthetic approach to a wide range of polycyclic aromatic compounds of diverse structural types. Specific polycyclic hydrocarbons synthesized by this route include benzo[a]- and benzo[c]fluorene, 7H-dibenzo[c,g]-, 13H-dibenzo[a,i]-, and 13H-dibenzo[a,g]fluorene, 15H-tribenzo[a,c,i]fluorene, dibenzo[b,def]chrysene, benzo[rst]pentaphene, indeno[1,2-b]fluorene, fluoreno[3,4-c]fluorene, octahydrodibenz[a,j]anthracene, dibenz[a,j]anthracene, octahydrodibenz[a,h]anthracene, dibenz[a,h]anthracene, dibenz[a,h]anthracene, picene, benzo[c]picene, 1H-benz[bc]aceanthrylene, and 4H-cyclopenta[def]chrysene. This method with appropriate modifications appears to be potentially broader in scope than established traditional methods of polycyclic hydrocarbon synthesis.