947725-04-4

White powder

Air and thermally stable alternative to DAST. Efficient deoxofluorinating agent for a wide variety of substrates.

The general procedure for the synthesis of 4-tert-butyl-2,6-dimethylphenyl sulfur trifluoride (Fluolead) from 1,2-bis(4-(tert-butyl)-2,6-dimethylphenyl) disulfide was as follows: in a flame-dried 500 mL round-bottom flask equipped with a dropping funnel, anhydrous acetonitrile (120 mL) was added and operated under nitrogen protection. Under stirring conditions, spray-dried potassium fluoride (29.1 g, 500 mmol) and bis(2,6-dimethyl-4-tert-butylphenyl) disulfide (19.4 g, 50 mmol) were added sequentially. Subsequently, the reaction mixture was cooled to 0 °C by an ice bath and bromine (26 mL, 500 mmol) was added slowly and dropwise. After the dropwise addition, the reaction mixture was continued to be stirred at 0 °C for 2 hours. After completion of the reaction, the solvent and excess bromine were removed under reduced pressure at room temperature. Finally, the product was purified by distillation under reduced pressure to give 17.5 g of light white solid in 70% yield. The product was characterized by 19FNMR (d-CH3CN): δ50.9 (t, J=62.7 Hz, 2F), -58.4 (d, J=62.7 Hz, 1F).

[1] Patent: US2012/83627, 2012, A1. Location in patent: Page/Page column 2
[2] Journal of the American Chemical Society, 2010, vol. 132, # 51, p. 18199 - 18205
[3] Patent: US7265247, 2007, B1. Location in patent: Page/Page column 11
[4] Patent: WO2008/13550, 2008, A1. Location in patent: Page/Page column 12
[5] Patent: US7265247, 2007, B1. Location in patent: Page/Page column 12