ChemicalBook CAS DataBase List 4,5,6-TRIFLUOROPYRIMIDINE

4,5,6-TRIFLUOROPYRIMIDINE synthesis

4synthesis methods

Product Name:4,5,6-TRIFLUOROPYRIMIDINE
CAS Number:17573-78-3
Molecular formula:C4HF3N2
Molecular Weight:134.06

1780-27-4

17573-78-3

The general procedure for the synthesis of 4,5,6-trifluoropyrimidine from 4,5,6-trichloropyrimidine was as follows: first, 7160 mL of cyclobutanesulfone and 3876 g of potassium fluoride (KF) were added to an autoclave and stirred for 1 hour at 150 °C. Subsequently, 700 mL of the cyclobutanesulfone was removed by reduced pressure distillation to dry the mixture. The mixture was cooled to 90 °C and the air in the kettle was replaced with nitrogen. Next, a solution of 3122 g of 4,5,6-trichloropyrimidine and 2386 g of dried cyclobutanesulfone preheated to 45 °C was added. The reaction vessel was sealed after the rapid addition of 10 g of CNC catalyst and 20.5 g of nitrobenzene. The mixture was heated to 200 °C and the reaction was stirred for 5 hours, then warmed to 220 °C to continue the reaction for 11 hours. The maximum total pressure was controlled at 6.5 bar during the reaction. Upon completion of the reaction, the mixture was cooled to 40 °C with stirring and the product was slowly depressurized and transferred to an ice-cold receiver. Subsequently, the internal temperature was slowly raised to 150 °C and the product was distilled first at atmospheric pressure and then at reduced pressure. Redistillation of the crude product gave 1540 g of 4,5,6-trifluoropyrimidine (66% of theoretical yield) as a colorless liquid.

1780-27-4 Synthesis

1780-27-4
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$11.00/100mg

17573-78-3
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$40.00/250mg

Yield: 66%

Reaction Conditions:

with potassium fluoride;nitrobenzene;1,3-dimethyl-2-(N',N',N",N"-tetramethylguanidino)-4,5-dihydro-3H-imidazolium chloride in sulfolane at 45 - 220; under 4875.49 Torr; for 17 h;

Steps:

2
Example 2; Preparation of 4,5,6-trifluoropyrimidine; 7160 ml of sulpholane and 3876 g of KF were initially charged in an autoclave and stirred at 150° C. for 1 h. Subsequently, the mixture was dried by distilling off 700 ml of sulpholane under reduced pressure. The mixture was then cooled to 90° C. and aerated with nitrogen, and a solution, heated to 45° C., of 3122 g of 4,5,6-trichloropyrimidine and 2386 g of dry sulpholane was pumped in. Afterwards, 166 g of CNC catalyst and 20.5 g of nitrobenzene were added rapidly and the vessel was sealed. The mixture was heated to 200° C. with stirring for 5 h and subsequently to 220° C. for 11 h. During the reaction, a maximum total pressure of 6.5 bar arose. The mixture was cooled to 40° C. with stirring and decompressed slowly into an ice-cooled receiver. The internal temperature was increased slowly to 150° C. and the product was distilled off initially at standard pressure, later under reduced pressure. After redistillation of the crude product, 1540 g of 4,5,6-trifluoropyrimidine (66% of theory) were obtained as a colourless liquid.

References:

Pleschke, Axel;Marhold, Albrecht US2006/9643, 2006, A1 Location in patent:Page/Page column 5

1780-27-4 Synthesis

1780-27-4
157 suppliers
$11.00/100mg

17573-78-3
119 suppliers
$40.00/250mg