RSS-Feed abonnieren
DOI: 10.1055/s-0028-1083197
Efficient and Versatile Synthesis of 2,3-Dialkylimidazo[4,5-b]quinolin-9-ols by Microwave-Assisted One-Pot Beckmann Rearrangement
Publikationsverlauf
Publikationsdatum:
23. Oktober 2008 (online)

Abstract
A direct microwave-assisted one-pot Beckmann rearrangement of 3-acyl-2-(alkylamino)quinolin-4-(1H)-ones in ethanol-pyridine (2:1) provides 2,3-dialkylimidazo[4,5-b]quinolin-9-ols as major products along with 2-alkyl-N-alkyloxazolo[4,5-c]quinolin-4-amines and 3-alkyl-N-alkylisooxazolo[4,5-c]quinolin-4-amines as minor products. Reactions of 3-acylquinolin-4-(1H)-ones containing secondary amine substituent at C-2 give 2-alkyloxazolo[5,4-b]quinolin-9-ols as major products via elimination of the secondary amine group. A mechanism proposed for the formation of Beckmann rearrangement products involves initial generation of a nitrilium ion intermediate, which is trapped either by the adjacent nitrogen of the γ-amino group to form imidazoquinolinols or by the oxygen of γ-hydroxy group of the tautomeric form of the ketoxime to form oxazoloquinolinamines.
Key words
microwave - one-pot Beckmann rearrangement - cyclization - imidazoquinolinol - oxazoloquinoline
- 1 Drug Data Rep. 2004, 26: 1059
- 2 Drug Data Rep. 2000, 22: 455
- 3
Boer R,Ulrich W.-R,Martin T, andGraedler U. inventors; PCT WO 076451 A1. ; Chem. Abstr. 2004, 141, 260751 - 4
Gerster JF,Lindstrom KJ,Marszalek GJ,Merrill BA,Mickelson JW, andRice MJ. inventors; PCT Int. Appl. WO 2000006577. ; Chem. Abstr. 2000, 132, 137381 - 5
Yoo KH.Choi EB.Lee HK.Yeon GH.Yang HC.Pak CS. Synthesis 2006, 1599 -
6a
Mihailovic ML.Rajkovic MM.Lorenc LB.Pavlovic VD.Milovanovic AZ.Tinant B.Declercq J.-P. Tetrahedron 1996, 52: 11995 -
6b
Lee-ruff E.Xi F.Qie JH. J. Org. Chem. 1996, 61: 1547 -
6c
Blanco JM.Caamano O.Fernandez F.Gomez G.Nieto I. Synthesis 1996, 281 -
6d
Toshihiko A.Toriumi Y.Mochizuki Y.Nonomura T.Nagaoka S.Furukawa K.Tsuru H.Adachi-Akahane S.Ohwada T. Bioorg. Med. Chem. 2006, 14: 8014 -
6e
Tong ST.Barker D. Tetrahedron Lett. 2006, 47: 5017 -
6f
Ahn JH.Shin MS.Jung SH.Kang SK.Kim KR.Rhee SD.Jung WH.Yang SD.Kim SJ.Woo JR.Lee JH.Cheon HG.Kim SS. J. Med. Chem. 2006, 49: 4781 -
6g
McKinnon DM.Abouzeid AA. J. Heterocycl. Chem. 1991, 28: 749 - 7 For the preparation of 2-alkylamino-3-acylquinolinones 1 from 2-alkylthio-3-acylquinolinones,
see:
Hwang BH.Park SH.Choi EB.Pak CS.Lee HK. Tetrahedron 2008, 64: 6698 - 8
Ren RX.Ou W. Tetrahedron Lett. 2001, 42: 8445 -
9a
Jeong TS.Kim MJ.Yu H.Kim KS.Choi JK.Kim SS.Lee WS. Bioorg. Med. Chem. Lett. 2005, 15: 1525 -
9b
Zhao YL.Chen YL.Chang FS.Tzeng CC. Eur. J. Med. Chem. 2005, 40: 792 -
9c
Trofimov BA.Zaitsev AB.Schmidt EY.Vasiltov AM.Mikhaleva AI.Ushakov IA.Vashchenko AV.Zorina NV. Tetrahedron Lett. 2004, 45: 3789 -
10a
Shi H. Synth. Commun. 2006, 36: 237 -
10b
Trofimov BA.Zaitsev AB.Schmidt EY.Vasil’tsov AM.Mikhaleva AL.Ushakov IA.Vashchenko AV.Zorina NV. Tetrahedron Lett. 2004, 45: 3789 - 11
Diez A.Voldoire A.Lopez I.Rubiralta M.Segarra V.Pages L.Palacios JM. Tetrahedron 1995, 51: 5143 - 12
Linderman RJ.Kirollos KS. Tetrahedron Lett. 1989, 30: 2049 - 13
Eshghi H.Hassankhani A. Org. Prep. Proced. Int. 2005, 37: 575 - 14
Cvetovich RJ.Chung JYL.Kress MH.Amato JS.Matty L.Weingarten MD.Tsay FR.Li Z.Zhou G. J. Org. Chem. 2005, 70: 8560 -
15a
Hajipour BR.Mallakpour SE.Imanzadeh G. J. Chem. Res., Synop. 1999, 228 -
15b
Kamakshi R.Reddy BSR. Aust. J. Chem. 2005, 58: 603 -
15c
Mitra AK.De A.Karchaudhuri N. J. Indian Chem. Soc. 1999, 76: 218 - 16
Bogdal D. In Microwave-assisted Organic Synthesis: One Hundred Reaction Procedures, Tetrahedron Organic Chemistry Series Vol. 25: Elsevier; Amsterdam: 2006. -
17a
Ghiaci M.Bakhtiari K. Synth. Commun. 2001, 31: 1803 -
17b
Touaux B.Texier-Boullet F.Hamelin J. Heteroat. Chem. 1998, 9: 351 -
18a
Delgado F.Cano AC.Garcia O.Alvarado J.Velasco L.Alvarez C.Rudler H. Synth. Commun. 1992, 22: 2125 -
18b
Das B.Srinivas KVNS.Madhusudhan P. International Electronic Conferences on Synthetic Organic Chemistry, November 1-30, 2003 Molecular Diversity Preservation International; Basel: 2003. p.1078 -
18c
Das B.Madhusudhan P.Venkataiah B. Synlett 1999, 1596 -
18d
Das B.Ravindranath N.Venkataiah B.Madhusudhan P. J. Chem. Res., Synop. 2000, 482 -
18e
Srinivas KVNS.Reddy EB.Das B. Synlett 2002, 625 -
18f
Firouzabadi H.Iranpoor N.Karimi B.Hazarkhani H. Synlett 2000, 263 -
18g
Gopalakrishnan M.Sureshkumar P.Kanagarajan V.Thanusu J. Lett. Org. Chem. 2005, 2: 444 -
18h
Eshghi H.Gordi Z. Synth. Commun. 2003, 33: 2971 -
19a
Loupy A.Regnier S. Tetrahedron Lett. 1999, 40: 6221 -
19b
Bhawal BM.Mayabhate SP.Likhite AP.Deshmukh ARAS. Synth. Commun. 1995, 25: 3315 -
19c
Fujita S.Koyama K.Inagaki Y. Synthesis 1982, 68 -
19d
Yamamoto K.Watanabe H. Chem. Lett. 1982, 1225 -
20a
Heuser S.Keenan M.Weichert AG. Tetrahedron Lett. 2005, 46: 9001 -
20b
Yoshinobu T.Yoshinobu G. Heterocycles 1987, 26: 2921 -
21a
Sun L.-Q.Chen J.Takaki K.Johnson G.Iben L.Mahle CD.Ryan E.XU C. Bioorg. Med. Chem. Lett. 2004, 14: 1197 -
21b
Stokker G. J. Org. Chem. 1983, 48: 2613 - 22
Yang Y.-H.Shi M. Tetrahedron 2006, 62: 2420 -
23a
Dubey PK.Kumar RV. Indian J. Chem., Sect B: Org. Chem. Incl. Med. Chem. 2000, 39: 746 -
23b
Katagiri N.Koshihara A.Atsume S.Kato T. J. Org. Chem. 1982, 47: 167 - 24
Kempter FE.Rokos H.Pfleiderer W. Chem. Ber. 1970, 103: 885 - 26
Bruker
SMART Version 5.6 Data Collection Software and SAINT Version 7.12A
Data Processing Software for the SMART APEX II System
Bruker
AXS Inc.;
Madison WI / USA:
2005.
- 27
Sheldrick GM. SHELXTL DOS/Windows/NT Version 6.14 Bruker AXS Inc.; Madison WI / USA: 2005.
References
X-ray crystal structure analysis of 2m, 3m, and 4m: atomic coordinates, bond lengths [Å] and angles [˚], anisotropic displacement parameters, hydrogen coordinates, torsion angles [˚] have been deposited at Cambridge Crystallographic Data Centre 12, Union Road, Cambridge CB2 1EZ, UK under deposition number CCDC 645836 for 2m, CCDC 646585 for 3m, and CCDC 647425 for 4m [fax: +44(1223)336 033, E-mail:deposit@ccdc.cam.ac.uk].