Dehydroamination Reaction of 9-Amino-9,10-dihydrophenanthrene and Related Compounds by Thermolysis

Article abstract of DOI:10.1246/bcsj.66.1451

Dehydroamination of 9-alkylamino-9,10-dihydrophenanthrene occurred at 190 - 250 deg C under non-basic conditions to give phenanthrene exclusively.The thermal reaction of cis-9-t-butylamino-10-methoxy-9,10-dihydrophenanthrene gave both 9-methoxyphenanthrene and 9-t-butylaminophenanthrene, while 9-aminophenanthrene was obtained from the thermal reaction of 9-amino-10-methoxy-9,10-dihydrophenanthrene.The thermal reaction of 9-amino-9,10-dihydroanthracene gave both anthracene and 9-aminoanthracene.Analysis of activation energies and frequency factors showed that the dehydroamination proceeds via an intramolecular proton transfer from C-10 to the amino group and subsequent C-N bond cleavage.