* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
With acetic acid; zinc In water at 75℃; for 1 h; Stirred
Zinc granules (30 g, 459 mmol) were added over 30 minutes to a solution of crude Intermediate 10 (25 g, 93 mmol) in acetic acid (400 mL) and water (100 mL) at 75° C., after which the mixture was stirred for an additional 1 hour. The suspension was cooled, filtered, and extracted with ethyl acetate (2.x.2 L). The combined organic extracts were washed with water (2.x.2 L), saturated NaHCO3 solution (2.x.500 mL), and brine (2.x.500 mL), dried over magnesium sulfate (MgSO4), and filtered. The solvent was removed under reduced pressure to yield a purple residue which was purified by flash column chromatography, eluting with hexanes/methylene chloride (1:1), to provide 6-bromoindole (Intermediate 11) as a blue-white powder (4.9 g, 27percent over two steps): TLC Rf (1:9 ethyl acetate/chloroform)=0.81. The proton NMR spectrum (300 MHz, CDCl3) was identical to the known compound.
Reference:
[1] Patent: US2003/225092, 2003, A1, . Location in patent: Page 12
[2] Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1981, p. 1679 - 1680
[3] Chinese Chemical Letters, 2010, vol. 21, # 8, p. 889 - 891
2
[ 78508-22-2 ]
[ 17826-04-9 ]
Reference:
[1] Chinese Chemical Letters, 2010, vol. 21, # 8, p. 889 - 891
3
[ 78508-22-2 ]
[ 5551-12-2 ]
Reference:
[1] Organic Preparations and Procedures International, 2006, vol. 38, # 3, p. 325 - 331
With sodium periodate In tetrahydrofuran; water at 20℃; for 2h;
With sodium periodate In tetrahydrofuran; water Aqueous phosphate buffer;
7.B
To a solution of crude (E)-2-(4-bromo-2-nitrophenyl)-N,N-dimethylethenamine (35.5 g, 131 mmol) in THF (300 mL) and pH 7.2 phosphate buffer (300 mL) was added NaIO4 (56.0 g, 262 mmol). The solids were removed and the filter cake was washed with EtOAc (200 mL). The filtrate was washed with brine (2 X 100 mL), dried and concentrated. The concentrate was purified via flash chromatography (5% EtOAc/hexanes to 10% EtOAc/hexanes) to provide 4-bromo-2- nitrobenzaldehyde (8.41 g, 28% yield).