1186
K. C. Lekhok et al.
References
on a Hitachi 026 CHN analyser; results were found to agree
well with calculated values.
1. Grunanger P, Vita-Finzi P (1991) In: Taylor EC, Weissberger A
(eds) Isoxazoles: part one in the chemistry of heterocyclic com-
pounds. Interscience, New York
2. Ning RY, Madan PB, Sternbach LH (1974) J Heterocycl Chem
11:107
3. Walder GN (1962) J Org Chem 27:1929
General procedure for the preparation
of 2-aminobenzophenones 3a-3e
To a well-stirred suspension of 10 g bakers’ yeast in
60 cm3 buffer solution (phosphate buffer 0.05 M, pH 7.0),
a solution of 0.5 g 3-phenyl-5-chloro-2,1-benzisoxazole in
20 cm3 methanol was added. The resulting mixture was
kept at room temperature with occasional shaking for 6 h
(monitored by TLC). After completion, the mixture was
filtered through a sintered glass funnel using celite. The
filtrate was extracted with dichloromethane (2930 cm3),
dried over anhydrous sodium sulfate, and on evaporation of
the solvent the product thus obtained was almost pure.
It was further purified by column chromatography using
n-hexane:ethyl acetate (4:1) as the eluent. The yield of the
2-amino-5-chlorobenzophenone (3a) was 87%. The pro-
duct was obtained as bright yellow crystals of mp 98 °C
([10] 99–100 °C). Similarly, other 2,1-benzisoxazoles were
reacted, and the corresponding 2-aminobenzophenones 3b–
3e were isolated in excellent yields (Table 1). The structure
of the products thus obtained were established by spec-
troscopic analysis and finally by comparison with authentic
samples prepared by following literature procedures [10].
4. Mamo A, Nicoletti S, Tai NC (2002) Molecules 7:618
5. Ubeda JI, Vilacampa M, Avendano C (1999) Synthesis 8:1335
6. Andronati SA, Pavlovskii VI, Kulikov OV, Simonov YA,
Gdanets M (2001) J Struct Chem 42:871
7. Fehnel EA (1996) J Org Chem 31:2899
8. Sternbach IH (1971) Angew Chem Int Ed Engl 10:34
9. Herrero S, Garcia-Lopez MT, Herranz R (2003) J Org Chem
68:4582 References cited therein
10. Welstead WJJ, Wayne HM, Stauffer HF, Turnbull LB, Sancilio
LF (1979) J Med Pharm Chem 22:1074
11. Walesh DA (1980) Synthesis 677–688
12. Davis RB, Pizzini LC (1884) J Org Chem 25:1884
13. Sternbach LH, Reeder E, Keller O, Metlesics W (1961) J Org
Chem 26:4488
14. Boruah RC, Sandhu JS, Thyagarajan G (1979) J Heterocycl
Chem 16:1087
15. Garattini S, Mussini E, Randall LO (1973) The benzodiazepines.
Raven Press, New York, p 1
16. Fan X, Zhang X, Zhang Y (2005) Heteroatom Chem 16:637
17. Angibaud PR, Venet MG, Filliers W, Broeckx R, Ligny YA,
Muller P, Poncelet VS, End DW (2004) Eur J Org Chem 479
18. Fan XS, Zhang YM (2002) Tetrahedron Lett 43:7001
19. Okabe M, Sun RC (1995) Tetrahedron 51:1861
20. Dormer PG, Eng KK, Farr RN, Humphren GR, McWilliams JC,
Jeider PJ, Sager JW, Volante RP (2003) J Org Chem 68:467
Reference cited therein
General procedure for bakers’ yeast-catalyzed
synthesis of 2-(alkylamino)benzophenones 3f–3i
21. Neubauer O, Fromherz KZ (1910) Physiol Chem 70:326
22. Neuberg C, Hirsch J (1921) Biochem Z 115:282
23. Servi S (1990) Synthesis 1–25
To a well-stirred suspension of 10 g bakers’ yeast in 60 cm3
buffer solution (phosphate buffer 0.05 M, pH 7.0), 0.5 g N-
methyl-3-phenyl-5-chloroanthranil methosulphate in 20 cm3
methanol was added. The resulting mixture was kept at room
temperature with occasional shaking for 8 h (monitored by
TLC). After complete conversion, the mixture was filtered
through a sintered glass funnel using celite. The filtrate was
extracted with dichloromethane (3930 cm3), dried over
anhydrous sodium sulfate, and concentrated on a rotary
evaporator to get the product 2-(methylamino)-5-chloroben-
zophenone (3f) in 92% yield. The product was obtained as
bright yellow crystals of mp 94 °C ([15] 94–95 °C), which
was further purified by column chromatography using petro-
leum ether:ethyl acetate (4:1) as the eluent. Similarly, other
2,1-benzisoxazolium salts 2g–2i were reacted, and the
corresponding 2-(alkylamino)benzophenones 3g–3i were
isolated in 85–92% yields (Table 1). The structures of the
products 3 thus obtained were established by spectroscopic
analysis and by comparison with authentic sample [15].
24. Takeuchi Y, Azuma K, Takakura K, Abe H, Harayama T (2000)
J Chem Soc Chem Commun 16:1643–1644
25. Csuk R, Glanzer BI (2000) In: Patel RN (ed) Stereoselective
biocatalysis, chapter 19. Marcel Dekker, New York
26. Li F, Cui J, Qian Zhang R (2004) J Chem Soc Chem Commun
21(20):2338–2339
27. Bonora GM, Drioli S, Forzato C, Nitti P, Pitacco G (2005) Lett
Org Chem 2:89
28. Lee JH (2005) Tetrahedron Lett 46:7329
29. Ocana AN, Olguin LF, Luna H, Estrada MJ, Barzana E (2001)
J Chem Soc Perkin Trans 1:2754
30. Kamal A, Rao MV, Rao AB (1990) Chem Lett 655. References
cited therein
31. Davey CL, Powell LW, Turner NJ, Wells A (1994) Tetrahedron
Lett 35:7867
32. Blackie JA, Turner NJ, Wells AS (1997) Tetrahedron Lett
38:3043
33. Baik W, Park TH (1995) J Org Chem 60:5683
34. Baik W, Rhee JU, Lee SH, Lee NH, Kim BH, Kim KS (1995)
Tetrahedron Lett 36:2793
35. Baruah M, Baruah A, Prajapati D, Sandhu JS (1996) Synlett
1193–1194
36. Gobbs DE, Barnes D (1990) Tetrahedron Lett 39:5555
37. Csuk R, Glanzer BI (1991) Chem Rev 91:49
38. Arrigo PD, Hogberg H–E, Fantoni G–P, Servi S (1994) Bioca-
talysis 9:299
Acknowledgments We thank the director of the North East Institute
of Science and Technology, Jorhat, for his keen interest and constant
encouragement to perform this work.
39. Hogberg H-E, Berglund P, Edlind H, Fagerhag J, Hedenstrom E,
Lundh M, Nordin O, Servi S, Vorde C (1995) Catal Today 22:591
123