Flexible application of Ethyl 6-bromobenzo[d]isoxazole-3-carboxylate in synthetic route

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 651780-27-7, and friends who are interested can also refer to it.

Rate laws may be derived directly from the chemical equations for elementary reactions. This is not the case, however, for ordinary chemical reactions.Ethyl 6-bromobenzo[d]isoxazole-3-carboxylate, cas is 651780-27-7,the Benzisoxazole compound, below Introduce a new synthetic route., 651780-27-7

20a) Ethyl 6-(4-hydroxyphenyl)-l,2-benzisoxazole-3-carboxylateEthyl 6-bromo-l,2-benzisoxazole-3-carboxylate (0.34 g, 1.26 mmol), (4- hydroxyphenyl)boronic acid (0.21, 1.51 mmol), tetrakis(triphenylphosphine)palladium (0) (0.06 g, 0.05 mmol) and 2 M sodium carbonate (5 mL) in 1 ,2-dimethoxyethane (6 mL) were stirred at 80 0C for 1 hour. The reaction mixture was diluted with water, followed by ethyl acetate. The layers were separated and the ethyl acetate layer was washed with brine, dried over magnesium sulfate, filtered, and concentrated to afford the crude material. The crude material was purified using hexanes: ethyl acetate (0 to 40% ethyl acetate) to afford a mixture of desired product, plus the free acid of the desired product, 6-(4-hydroxyphenyl)-l,2- benzisoxazole-3-carboxylic acid. All the fractions were combined and concentrated. The mixture was then dissolved in ethanol. Thionyl chloride was added, and the reaction mixture was reflux for 8 days. The reaction mixture was cooled to room temperature and concentrated. The concentrated material was diluted with 5% sodium bicarbonate, and extracted with ethyl acetate. The ethyl acetate layer was washed with water followed by brine, dried over magnesium sulfate, filtered, and concentrated. The crude material was purified using hexanes: ethyl acetate (0 to 100% ethyl acetate) to afford 0.044 g (13%) of ethyl 6-(4-hydroxyphenyl)- 1 ,2-benzisoxazole-3- carboxylate. 1H NMR (400 MHz, d6-DMSO): delta 9.76 (s, IH), 8.05 (m, 2H), 7.79 (dd, J = 8, 1 Hz, IH), 7.65 (d, J = 9 Hz, 2H), 6.88 (d, J = 9 Hz, 2H), 4.47 (q, J = 7 Hz, 2H), 1.39 (t, J = 7 Hz, 3H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 651780-27-7, and friends who are interested can also refer to it.

Reference£º
Patent; SMITHKLINE BEECHAM CORPORATION; WO2008/157270; (2008); A1;,
Benzisoxazole – Wikipedia
Benzisoxazole – an overview | ScienceDirect Topics