Example 1
548.7 g Keystone™ liquid pyranine solution and 100.1 g of methanol were charged to a 1 L multi-neck round bottom flask equipped with mechanical agitator, thermocouple, methallyl chloride dosing line, NaOH 50% dosing line, and condenser. The mixture was heated to 70° C. and upon reaching the reaction temperature slow additions of methallyl chloride and NaOH 50% were begun. The reaction mixture was refluxed at 70-72° C. during the addition. The methallyl chloride was added over 4 hours while the 50% NaOH was added over 6 hr period, for addition rates of about 7 g/hr and 5 g/hr, respectively. After addition of the NaOH, 50% solution was complete, the reaction mixture was held at 70° C. for 2 more hours. The methanol was removed by distillation at 70-75° C. under nitrogen sparging. Approximately 120 g of distillate was removed.
Table 1 summarizes the material balance of the initial reaction mixture.
Table 2 sets forth the composition of the reaction product after distillation, as determined by NMR.
The unfunctionalized pyranine content was 1.4 mol % of the total moles of unfunctionalized pyranine, methallyl oxy pyranine and methallyl pyranine.
