Yield:137-08-6 96%

Reaction Conditions:

Stage #1: calcium beta-alaninate in ethanol at 75; for 6 h;
Stage #2: D-pantolactone in ethanol at 75; for 16 h;Temperature;

Steps:

14 xample 11 Synthesis of calcium D-pantothenate

The solid of Example 5 was added to a 10-L jacketed mechanically stirred glass reactor, 5 L of ethanol was added, and the mixture was thoroughly stirred by mechanical stirring (200 rpm).69.2 g of metal calcium (molar ratio of β-aminopropionic acid and metal calcium was 2:1.02) was added thereto, and the temperature of the reaction vessel was controlled to 75 ° C by a constant temperature water bath, and the reaction was refluxed for 6 hours, and the reaction liquid was filtered.444.5 g of D-pantolactone was added to the filtrate, and the mixture was thoroughly stirred by mechanical stirring (200 rpm), and the temperature of the reaction vessel was controlled to 75 ° C by a constant temperature water bath, and the reaction was refluxed for 16 hours.During the period, the consumption of D-lactone was monitored by HPLC to follow the progress of the reaction. After the reaction was completed, the reaction solution was filtered, and the filtrate was concentrated and dried to obtain 0.776 kg of calcium D-pantothenate, and the yield was 96%.The measured calcium content was 8.6% and the specific rotation was +26.2.

References:

CN107986979,2018,A Location in patent:Paragraph 0049-0054; 0064; 0065; 0066; 0067; 0068; 0069