Abstract
The room temperature ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4), is used as a ‘green’ recyclable alternative to classical molecular solvents for the cyclocondensation of α-bromoketones with 2-aminopyridine to form 2-arylimidazo[1,2-a]pyridines with rate accelerations and improved yields.
References
1.
(a)
Welton T.
, Chem. Rew. , 1999 , 99 , 2071 .
2.
Wassercheid P.
, and
Keim W.
, Angew. Chem. Int. Ed. Engl. , 2000 , 39 , 3772 .
3.
Freemantle M.
, Chem. Eng. News , 2001 , 79 (1 ), 21 .
4.
Dupont J.
,
de Souza R. F.
,
Suarez P. A. Z.
, Chem. Rev. , 2002 , 102 , 3667 .
5.
Zhao D.B.
,
Wu M.
,
Kou Y.
, and
Min E.
, Catalysis Today , 2002 , 74 , 157 .
6.
Xie Y.Y.
,
Chen Z. C.
, and
Zheng Q. G.
Synthesis , 2002 , 11 , 1505 . We prepared imidazo[1,2-a]pyridine by reaction of α-tosyloxyketones with 2-aminopyridine
7.
Dubinsky B.
,
Shriver D. A.
,
Sanfilippo P. J.
,
Press J. B.
,
Tobia A. J.
, and
Rosenthale M. E.
, Drug. Dev. Res. , 1990 , 21 , 277 .
8.
(a)
Katsura Y.
,
Nishino S.
,
Inoue Y.
,
Tomoi M.
, and
Takasugi H.
, Chem. Pharm. Bull. , 1992 , 40 , 371 .
9.
Starrett J.E.
,
Montzka T. A.
,
Crosswell A. R.
, and
Cavanagh R. L.
, J. Med. Chem. , 1989 , 32 , 2204 .
10.
Louis E.C.
, U. S. 2785133, cf. C.A.: 1957 , 51 , P9175a.
11.
Fisher M.H.
, and
Lusi A.
, J. Med. Chem. , 1972 , 15 , 982 .
12.
Tomoda H.
,
Hirano T.
,
Saito S.
,
Mutai T.
, and
Araki K.
, Bull. Chem. Soc. Jap. , 1999 , 72 , 1327 .
13.
(a)
Bonhôte P.
,
Dias A. P.
,
Papageorgiou N.
,
Kalyanasundaram K.
, and
Grätzel M.
, Inorg. Chem. , 1996 , 35 , 1168 .
14.
Suarez P.A. Z.
,
Dillius J. E. L.
,
Einloft S.
,
de Souza R. F.
, and
Dupont J.
, Polyhedron , 1996 , 15 , 1217 .
15.Beilstein 28 I 62, II 239.
16.
Balon Ya. G.
,
Shulman M. D.
,
Smirnov V. A.
,
Yukhnomenko M. M.
, and
Yukhomenko M. A.
, Zh. Org. Khim. , 1990 , 26 , 1566 .
17.
Katritzky A.R.
,
Qiu G. Q.
,
Long Q. H.
,
He H. Y.
, and
Steel P. J.
, J. Org. Chem. , 2000 , 65 , 9201 .
18.
Artyomov V.A.
,
Shestopalov A. M.
, and
Litvinov V. P.
, Synthesis , 1996 , 8 , 927 .
19.
Buu-Hoï Ng. Ph.
,
Hóan Ng.
, and
Royer R.
, Bull. Soc. Chim., Fr , 1950 , 489 –493 .
20.
Royer R.
,
Bisagni E.
, and
Hudry C.
, Bull. Soc. Chim. Fr , 1961 , 933 –938 .