SYNTHESIS OF SUBSTITUTED 2-PHENYLBENZOTHIAZOLES
3031
124.03, 122.26, 122.06, 116.06. Anal. calculated for C13H9NOS: C, 68.70; H, 3.99; N,
6.16. Found: C, 68.43; H, 4.05; N, 6.25.
Typical Synthesis of 4-Bromophenylbenzothiazole (3g)
(Microwave Conditions)
A homogenous mixture of 2-aminothiophenol (0.33 mL, 3.13 mmol), 4-bromo-
benzaldehyde (0.58 g, 3.16 mmol), and sodium metabisulfite (0.60 g, 3.16 mmol) in
DMSO (2 mL) was irradiated in a sealed tube at 120 ꢀC for 25 min by moderating
the initial power (100 W). The reaction mixture was allowed to cool to room
temperature, excess water was added, and the solid precipitate was collected by
filtration. The precipitate was washed with excess water and dried to give
1
4-bromobenzothiazole (3g) in 82% yield. Mp 127–129 ꢀC (lit.[11] 132 ꢀC). H NMR
(500 MHz; CDCl3) 8.10 (1H, d, J 8.0 Hz, H-4), 7.99 (2H, d, J 7.5 Hz, H-30, H-50),
7.93 (1H, d, J 8.0 Hz, H-7), 7.65 (2H, d, J 7.5 Hz, H-20, H-60), 7.53 (1H, t,
J 8.0 Hz, H-6), 7.43 (1H, t, J 8.0 Hz, H-5). 13C NMR (125 MHz, CDCl3) 166.69,
154.11, 135.07, 132.59, 132.25, 128.92, 126.51, 125.46, 125.42, 123.35, 121.67. Anal.
calcd. for C13H8BrNS: C, 53.81; H, 2.78; N, 4.82. Found: C, 53.91; H, 2.78; N, 4.70.
ACKNOWLEDGMENTS
We thank the Welsh School of Pharmacy, Cardiff University, for PhD student-
ship funding (ADW=AAW), and the BBSRC (BB=D524140) for research grant
funding (MCB=MCD).
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