PAPER
Bromination of Primary Aromatic Amine Derivatives
223
Anal. Calcd for C11H10BrNO3 (284.1): C, 46.50; H, 3.55; N, 4.93.
Found: C, 46.62; H, 3.41; N, 5.01.
7b
Waxy solid.
IR (Nujol): 1780, 1715, 1607 cm–1.
1H NMR (CDCl3, 200 MHz): = 2.93 (s, 4 H), 6.65 (s, 1 H), 7.29
Benzylic Monobromination and gem-Dibromination of 5a–c
To a stirred solution of the appropriate succinimide 5a–c (5 mmol)
in CCl4 (40 mL) was added dropwise a solution of Br2 (6.25 mmol)
in CCl4 (10 mL) at r.t. over a period of 10 min to 15 min and the
mixture was further stirred for 4 h at r.t. The mixture was concen-
trated in vacuo and the residue was dissolved in EtOAc (50 mL).
The organic layer was washed with H2O, 5% aq NaHSO3, H2O,
brine and dried (Na2SO4). Concentration of the organic layer in vac-
uo furnished the desired monobromo products 6a–c in 92–94%
yields. Similarly the starting materials 5a–c (5 mmol) with Br2 (12.5
mmol) on refluxing in CCl4 (50 mL) for 8 h gave the gem-dibromo
compounds 7a–c in 94–96% yields. The 1H NMR spectra of isolat-
ed monobromo products 6a–c revealed that 2–3% of starting mate-
rials remain unreacted and/or the formation of corresponding gem-
dibromo products. The analytically pure products were obtained by
further recrystallisation.
(d, J = 8 Hz, 1 H), 7.40–7.70 (m, 3 H).
MS: m/z = 349, 347, 345, 268, 266, 210, 187, 158, 130, 117, 103, 89.
Anal. Calcd for C11H9Br2NO2 (347.0): C, 38.07; H, 2.61; N, 4.04.
Found: C, 37.88; H, 2.43; N, 4.02.
7c
Mp 212–213 °C (EtOAc).
IR (Nujol): 1774, 1707, 1603 cm–1.
1H NMR (CDCl3, 200 MHz): = 2.93 (s, 4 H), 6.65 (s, 1 H), 7.35
(d, J = 8 Hz, 2 H), 7.69 (d, J = 8 Hz, 2 H).
13C NMR (acetone-d6, 50 MHz): = 29.2, 41.6, 127.8, 127.9, 135.2,
142.8, 177.0.
MS: m/z = 349, 347, 345, 268, 266, 210, 184, 158, 130, 104, 77, 63.
6a
Anal. Calcd for C11H9Br2NO2 (347.0): C, 38.07; H, 2.61; N, 4.04.
Found: C, 37.97; H, 2.58; N, 3.76.
Mp 126–128 °C (CCl4).
IR (Nujol): 1782, 1717, 1595 cm–1.
1H NMR (CDCl3, 200 MHz): = 2.96 (d, J = 2 Hz, 4 H), 4.38 (s, 2
H), 7.17 (d, J = 6 Hz, 1 H), 7.30–7.65 (m, 3 H).
Acknowledgements
A. K. thanks CSIR, New Delhi, for the award of a research fel-
lowship. N. P. A. thanks Department of Science and Technology,
New Delhi, for financial support. We thank Dr. K. N. Ganesh, Head,
Division of Organic Chemistry (Synthesis), for constant encourage-
ment.
MS: m/z = 269, 267, 188, 160, 142, 132, 118, 104, 91, 77, 63.
Anal. Calcd for C11H10BrNO2 (268.1): C, 49.28; H, 3.76; N, 5.23.
Found: C, 49.11; H, 3.58; N, 5.08.
6b
Mp 97–100 °C (CHCl3).
IR (CHCl3): 1782, 1718, 1610 cm–1.
References
1H NMR (CDCl3, 200 MHz): = 2.90 (s, 4 H), 4.50 (s, 2 H), 7.20–
7.55 (m, 4 H).
(1) NCL Communication No. 6615.
(2) (a) Kirk–Othmer Encyclopedia of Chemical Technology, 4th
ed., Vol.2; Kirk, R. E.; Othmer, D. F., Eds.; Wiley: New
York, 1991, 426. (b) Ullmann’s Encyclopedia of Industrial
Chemistry, 5th ed., Vol. A2; Ullmann, F.; Gerhartz, W.;
Yamamoto, Y. S.; Campbell, F. T.; Pfefferkorn, R.;
Rounsaville, J. F., Eds.; VCH: Weinheim, 1985, 303.
(c) Vogel, A. I. Vogel’s Textbook of Practical Organic
Chemistry, 5th ed.; Furniss, B. S.; Stanley, B., Eds.;
Longman: Harlow, 1989, Chap. 6, 824. (d) March, J.
Advanced Organic Chemistry, 4th ed.; Wiley: New York,
1992, Chap. 11, 501. (e) Morrison, R. T.; Boyd, R. N.
Organic Chemistry, 6th ed.; Prentice-Hall: New Delhi,
1996, Chap. 15, 517. (f) Morrison, R. T.; Boyd, R. N.
Organic Chemistry, 6th ed.; Prentice Hall: New Delhi, 1996,
Chap. 22, 821. (g) Morrison, R. T.; Boyd, R. N. Organic
Chemistry, 6th ed.; Prentice-Hall: New Delhi, 1996, Chap.
23, 845.
MS: m/z = 269, 267, 188, 160, 146, 132, 106, 91, 77, 65.
Anal. Calcd for C11H10BrNO2 (268.1): C, 49.28; H, 3.76; N, 5.23.
Found: C, 49.15; H, 3.82; N, 5.36.
6c
Mp 186-187 °C (EtOAc).
IR (Nujol): 1778, 1700, 1600 cm–1.
1H NMR (CDCl3, 200 MHz): = 2.90 (s, 4 H), 4.50 (s, 2 H), 7.29
(d, J = 8 Hz, 2 H), 7.51 (d, J = 8 Hz, 2 H).
13C NMR (CDCl3, 50 MHz): = 28.4, 32.3, 126.7, 129.8, 131.8,
138.1, 175.9.
MS: m/z = 269, 267, 188, 132, 106, 89, 77.
Anal. Calcd for C11H10BrNO2 (268.1): C, 49.28; H, 3.76; N, 5.23.
Found: C, 49.16; H, 3.70; N, 5.19.
(3) Gassman, P. G.; Drewes, H. R. J. Am. Chem. Soc. 1978, 100,
7600.
7a
(4) Ayyangar, N. R.; Kalkote, U. R.; Nikrad, P. V. Tetrahedron
Lett. 1982, 23, 1099.
Mp 200–203 °C (CHCl3).
IR (Nujol): 1771, 1709, 1595 cm–1.
(5) Ref.,2a see page 437.
(6) Argade, N. P.; Balasubramaniyan, V. Heterocycles 2000, 53,
475; and references cited therein.
(7) (a) Mhaske, S. B.; Argade, N. P. J. Org. Chem. 2002, 67.
(b) Mangaleswaran, S.; Argade, N. P. J. Chem. Soc., Perkin
Trans. 1 2001, 1764. (c) Mangaleswaran, S.; Argade, N. P.
J. Org. Chem. 2001, 66, 5259. (d) Deshpande, A. M.; Natu,
1H NMR (CDCl3, 200 MHz): = 2.99 (d, J = 2 Hz, 4 H), 6.55 (s, 1
H), 7.05 (dd, J = 8, 2 Hz, 1 H), 7.45 (dt, J = 8, 2 Hz, 1 H), 7.57 (dt,
J = 8, 2 Hz, 1 H), 8.12 (dd, J = 10, 2 Hz, 1 H).
MS: m/z = 349, 347, 345, 268, 266, 186, 158, 130, 103, 76.
Anal. Calcd for C11H9Br2NO2 (347.0): C, 38.07; H, 2.61; N, 4.04.
Found: C, 37.93; H, 2.55; N, 3.81.
Synthesis 2002, No. 2, 221–224 ISSN 0039-7881 © Thieme Stuttgart · New York