Abstract
A ligand-free or carrier-free copper salt system that catalysed aerobic oxidative coupling of 2-naphthols has been established. 1,1′-Bi-2-naphthols were afforded in excellent yields in methanol in the presence of 5 mol % copper (| or ||) salts. The coupling reaction could also be performed very well in aqueous solvents.
References
1.
For reviews, see, e.g. : (a)
Chen Y.
,
Yekta S.
, and
Yudin A. K.
, Chem. Rev. , 2003 , 103 , 3155 .
2.
Pu L.
, Chem. Rev. , 1998 , 98 , 2405 .
3.
Kaupp G.
, Angew. Chem. Int. Ed. Engl. , 1994 , 33 , 728 .
4.
Kagan H.B.
, and
Riant O.
, Chem. Rev. , 1992 , 92 , 1007 .
5.
Rosini C.
,
Franzini L.
,
Raffaelli A.
, and
Salvadori P.
, Synthesis , 1992 , 503 .
6.
(a)
Toda F.
,
Tanaka K.
, and
Iwata S.
, J. Org. Chem. , 1989 , 54 , 3007 .
7.
Ding K.
,
Wang Y.
,
Zhang L.
,
Wu Y.
, and
Matsuura T.
, Tetrahedron , 1996 , 52 , 1005 .
8.
Yamamoto K.
,
Fukushima H.
,
Okamoto Y.
,
Hatada K.
, and
Nakazaki M.
, J. Chem. Soc., Chem. Commun. , 1984 , 1111 .
9.
Feringa B.
, and
Wynberg H.
, Tetrahedron Lett. , 1977 , 18 , 4447 .
10.
Sakamoto T.
,
Yonehara H.
, and
Pac C.
, J. Org. Chem. , 1997 , 62 , 3194 .
11.
Nakajima M.
,
Miyoshi I.
,
Kanayama K.
, and
Hashimoto S.
, J. Org. Chem. , 1999 , 64 , 2264 .
12.
Hwang D.R.
,
Chen C. P.
, and
Uang B. J.
, Chem. Commun. , 1999 , 1207 .
13.
Sharma V.B.
,
Jain S. L.
, and
Sain B.
, J. Mol. Catal. A: Chem. , 2004 , 219 , 61 .
14.
Chen L.
,
Lan J. B.
,
Mao Z. H.
,
Yu X. Q.
, and
Xie R. G.
, Chin. Chem. Lett. , 2004 , 15 , 903 .
15.
(a)
Lan J.B.
,
Chen L.
,
Yu X. Q.
,
You J. S.
, and
Xie R. G.
, Chem. Commun. , 2004 , 188 .
16.
Lan J.B.
,
Zhang G. L.
,
Yu X. Q.
,
You J. S.
,
Chen L.
,
Yan M.
, and
Xie R. G.
, Synlett , 2004 , 1905 .