ChemicalBook CAS DataBase List 2,3,5,6-Tetrafluorophenol

2,3,5,6-Tetrafluorophenol synthesis

10synthesis methods

Product Name:2,3,5,6-Tetrafluorophenol
CAS Number:769-39-1
Molecular formula:C6H2F4O
Molecular Weight:166.07

50-01-1

(E)-1-(perfluorophenyl)-3-phenylprop-2-en-1-one

54081-33-3

140-10-3

769-39-1

2-amino-4-phenyl-4,5-dihydro-1H-pyrimidin-6-one

6340-72-3

Chalcone 1d (1.0 g, 3.4 mmol) was added to a 10 mL DMF solution containing guanidine hydrochloride (0.64 g, 6.7 mmol) and sodium hydride (0.32 g, 13.4 mmol). The reaction mixture was stirred at 50 °C for 1.5 h before being cooled to room temperature and subsequently poured into ice water and extracted with ethyl acetate. Undissolved material at the phase boundary was removed by filtration, resulting in the isolation of 2-amino-6-phenyl-5,6-dihydropyrimidin-4(1H)-one (7a, 0.1 g, 16% yield). The 1H NMR data and melting point (255-257 °C; literature value 257.3 °C [19]) of this product were in agreement with those reported in the literature [19]. The extract was washed with water and dried with CaCl2 and concentrated under reduced pressure to remove the solvent, yielding 0.29 g of residue, which was analyzed by NMR and GC/MS.

602-94-8
340 suppliers
$7.00/10g

769-39-1
259 suppliers
$10.00/1g

Yield:769-39-1 95%

Reaction Conditions:

Stage #1: Pentafluorobenzoic acidwith sodium acetate in N,N-dimethyl-formamide; for 6 h;Reflux;
Stage #2: with sulfuric acid in N,N-dimethyl-formamide at 80; pH=< 1; for 5 h;Reflux;Solvent;Reagent/catalyst;Temperature;

Steps:

1-5 Example 4:

Put 404 grams of DMF and 202.3 grams of sodium acetate into a 1L glass reactor. Add 106.0 g of pentafluorobenzoic acid at a temperature of 50-55 °C. The reaction was heated and refluxed for 6 hours. HPLC detected that the raw material content of the reaction solution was lower than 1.0%, and dropped below 80 °C, and 143.8 g of 98% concentrated sulfuric acid was added to the kettle to adjust the pH to less than 1. Then the temperature was raised and refluxed for 5 hours. After the reflux is completed, steam distillation is performed to separate the lower organic matter. The lower organic matter was rectified to obtain 79.0 g of 2,3,5,6-tetrafluorophenol, which turned into white crystals after cooling, with a yield of 95% and a purity of 99.8%.

References:

CN113214050,2021,A Location in patent:Paragraph 0023-0032

652-34-6 Synthesis