301823-87-0Relevant articles and documents
Catalytic aerobic oxidative coupling of some simple phenols and natural phenanthrols with CuCl(OH).TMEDA
Majumder,Chakraborty,Roychowdhury
, p. 389 - 393 (2007/10/03)
Aerobic oxidative coupling of phenol, catechol, resorcinol and pyrogallol with CuCl(OH).TMEDA as catalyst affords 2',4-dihydroxybiphenyl (1a), 3,3',4,4'-tetrahydroxybiphenyl (2a), 2,2',4,4'-tetrahydroxybiphenyl (3a) and 2,2',4,6'-tetrahydroxybiphenyl (4a) and 2',3,3',4,4',5-hexahydroxybiphenyl (5a), respectively, in moderate yields. Similar catalytic aerobic oxidative coupling of the naturally occurring phenanthrols, nudol (6a) [2,7-dihydroxy-3,4-dimethoxyphenanthrene], 2,7-dihydroxy-3,4,6-trimethoxyphenanthrene (6b) and cirrhopetalin (7) [7-hydroxy-4-methoxy-2,3-methylenedioxyphenanthrene] with the same reagent gives the corresponding 1,1'-biphenanthryls 8a and 8c and the 8,8'-biphenanthryl 9a, respectively, in very good yields. All these reactions exhibit a high degree of regioselectivity.