* 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.
4,6-bis(4-nitro-3-hydroxy-2,5,6-trifluorophenoxy)pyrimidine[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
94%
With hydrogenchloride; potassium carbonate; In nitrogen; water; dimethyl sulfoxide; ethyl acetate;
EXAMPLE 5 Preparation of 4,6-bis(4-nitro-3-hydroxy-2,5,6-trifluorophenoxy)pyrimidine STR12 11.2 g of <strong>[1193-24-4]4,6-dihydroxypyrimidine</strong> (0.1 mol) and 42.6 g of pentafluoronitrobenzene (0.2 mol) are dissolved in 400 ml of dimethyl sulfoxide in a 2 l three-neck flask fitted with nitrogen inlet and stirrer. 60 g of potassium carbonate (0.43 mol) are added in portions to the solution. The mixture is then stirred at room temperature for 24 hours and then heated in a temperature-controllable oil bath at 60 C. for 4 hours and, after the addition of 30 g of potassium hydrogen-carbonate (0.3 mol), for a further 6 hours. The reaction solution is then allowed to cool to room temperature, and the residue is filtered off via a Buchner funnel. After 500 ml of water and 300 ml of ethyl acetate has been added, concentrated hydrochloric acid is added drop wise until the solution is acidic. The organic phase is then washed three times with water, dried over sodium sulfate and evaporated to half in a rotary evaporator. After 2 days, the precipitated orange-brown crystals are filtered off, washed with petrol ether and dried for 48 hours under nitrogen at 40 C./10 mbar in a vacuum drying cabinet (yield: 94%). Characterization: Mass spectrum: molecular peak at 494
In methanol; water;Product distribution / selectivity;
Example 5: Preparation of <strong>[4773-96-0]mangiferin</strong> monopotassiumMangiferin 42.2(0. lmol) is suspended in the mixture of water 1000ml and methanol 1000ml in reactor ,mixing round adequately. Potassium bicarbonate 10.0g(0. lmol) is dissolved in water , the concentration is 0.1 %( w/v) . The solution of potassium bicarbonate is added slowly into the <strong>[4773-96-0]mangiferin</strong> suspended solution while mixing round until the solution is clear , then the reaction solution is filtrated, appropriate quantity ethanol-dichloroform (7: 1 v/v) is added into the reaction solution, mixing round adequately . A lot of deposition is come into being , the reaction solution is filtrated to get the depositon, the solid substance is heated up no excess 60 C to dry .The yellow substance is <strong>[4773-96-0]mangiferin</strong> monopotassium . Its weight is 31.7g, the productivity is 75%. The purity of <strong>[4773-96-0]mangiferin</strong> monopotassium is 98.7% detected by HPLC.
Resorcinol (1.1g, 10 mmol) and anhydrous potassium bicarbonate (2.5g, 25 mmol) was mixed in a closed pyrex tube and heated at 210 C for 3 hours. Then mixture was cooled to room temperature and treated with water (50 ml). The resulting dark brown solution was transferred in to a 250 ml erlenmeyer flask and treated with conc. HCl dropwise slowly while occasional cooling and stirring. Conc. HCl addition was stopped upon disappearance of bubbling from the solution. This solution was allowed to settle overnight and yellow colored solid product formed in the bottom of the flask was collected by vacuum filtration. Crude product was recrystallized with 1000 ml of boiling water and 0.79 g (72percent) of the crystalline yellow product 7 was obtained.
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
For Research Only
120K+ Compounds
Competitive Price
1-2 Day Shipping
