Potassium carbonate-sesquihydrate

To the mixture of 41.0 g (lS,2S)-2-[2- [3-(lH-benzimidazol-2-yl)propyl]methylmethylamino ethyl]-6-fluoro-l-isopropyl-l,2,3,4-tetrahydronaphthalen-2-ol, 240 mL water, and 240 mL toluene were added 22.4 g potassium hydroxide, and the mixture heated to 45-50°C for one hour. The resulting two-phase mixture was separated. To the organic phase was added 39.4 g (4.0 eq.) potassium carbonate sesquihydrate then a solution of 21.0 g (17.7 mL, 3.25 eq.) methoxyacetyl chloride in 33 mL toluene was added over two hours at 25-30°C, and the resulting mixture stirred for an additional 30 min. Water, 200 mL, was added to quench the reaction. The organic phase, containing mibefradil as the free base was added an ethanol. 

Methyl isocyanoacetate (14 0.728 mL, 8.00 mmol) in DMF (3 mL) was added to a stirred suspension of (5)-3-(4-(benzyloxy)phenyl)-2-((/ert-butoxycarbonyl)amino)propanoic acid (63 743 mg, 2.00 mmol) and potassium carbonate sesquihydrate (661 mg, 4.00 mmol) in DMF (4 mL) at ambient temperature and the resulting mixture was stirred at ambient temperature for 5 min, then cooled to 0 °C. Diphenyl phosphorazidate (DPPA 0.474 mL, 2.2 mmol) in DMF (3 mL) was added, and the resulting mixture was stirred at 0 °C for 2 h, then at ambient temperature for 14 h. The reaction mixture was subsequently diluted with 1 1 benzene/ethyl acetate (150 mL) and sequentially washed with 30-mL portions of water, 10% aqueous citric acid, water, and saturated aqueous sodium bicarbonate. The organic layer was then dried over magnesium sulfate, filtered, and concentrated in vacuo. Purification of the residue... 

Potassium carbonate sesquihydrate K2C03 I.6H2O 6381-79-9 166.229 granuiar cry 111 ... 

According to J. J. Pohl, potassium sesquihydrated carbonate loses S-59 per cent, of water at 100°, and forms monohydrated potassium carbonate, K2CO,.HaO, which at 130°-135°... 

The following table provides data on the common salts used for salting out in chromatographic headspace analysis, as applied to direct injection methods and to solid phase microextraction.1 2 Data are provided for the most commonly available salts, although others are possible. Sodium citrate, for example, occurs as the dihydrate and the pentahydrate. The pentahydrate is not as stable as the dihydrate, however, and dries out on exposure to air, forming cakes. Potassium carbonate occurs as the dihydrate, trihydrate, and sesquihydrate however, data are provided only for the anhydrous material. The solubility is provided as the number of grams that can dissolve in 100 ml of water at the indicated temperature. The vapor enhancement cited is the degree of increase of the concentration of vapor over the solution of a 2% (mass/mass) ethanol solution in water at 60°C.3... 

Potassium carbonate (poe-TAS-ee-yum KAR-bun-ate) is also known as potash, pearl ash, salt of tartar, carbonate of potash, and salt of wormwood. It is a white, translucent, odorless, granular powder or crystalline material that tends to absorb water from the air. As it does, it is converted into the sesquihydrate ( sesqui = one-and-a-half) with the formula KjCOj i.sHjO. That formula means that three molecules of potassium carbonate share two molecules of water among them. 

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