تفاعل #1117642

معادلة التفاعل

NAD+

thiophosgene

sodium carbonate

→

NAD NCS

المذيبات

H2O

CHCl3

ظروف التفاعل

المعالجة

1. 1
   أخرىwith attached bubble-counter
2. 2
   workup.ADDITIONa little Na2CO3 was added
3. 3
   workup.WAITAfter 3.5 hours there was no longer
4. 4
   أخرىThe mixture was evaporated to dryness in vacuo
5. 5
   أخرىfreeze-dried
6. 6
   أخرىThe slightly brownish product mixture could be purified of by-products by column chromatography on silica gel
7. 7
   أخرىunpurified for the reaction with the polymer (see Example 2)
8. 8
   ترشيحsince purification by ultrafiltration of the product

الإجراء التجريبي

2 mmol of NAD+ were dissolved in 10 ml of H2O in a round-bottomed flask with attached bubble-counter, and a little Na2CO3 was added. A solution of 20 mmol of thiophosgene in 10 ml of CHCl3 was added with vigorous stirring at 20° C. The pH was checked every 10 minutes and kept between 5.5 and 8.5 by the addition of small amounts of sodium carbonate. After 3.5 hours there was no longer any change in the pH, and no further gas was evolved. The mixture was evaporated to dryness in vacuo and freeze-dried. The slightly brownish product mixture could be purified of by-products by column chromatography on silica gel using water/acetonitrile as eluent. However, it is advisable to use the product mixture unpurified for the reaction with the polymer (see Example 2), since purification by ultrafiltration of the product immobilized on the polymer is considerably more straightforward and, moreover, the sensitivity of NAD-NCS results in losses due to dimerization and trimerization during purification.

المصدر