DifluoroiodoMethyl phenyl sulfone Chemical Properties

Boiling point:

312.4±42.0 °C(Predicted)

Density 

1.975±0.06 g/cm3(Predicted)

storage temp. 

2-8°C(protect from light)

Appearance

White to off-white Solid

Safety Information

Safety Statements 

24/25

HS Code 

29309090

DifluoroiodoMethyl phenyl sulfone Usage And Synthesis

Description

A visible light-catalysed direct and regioselective (phenylsulfonyl) difluoromethylation of imidazo[1,2-A]pyridines and benzo[d]-imidazo[2,1-b]thiazoles was carried out by DifluoroiodoMethyl phenyl sulfone under mild conditions. This synthetic methodology enables the introduction of a CF2SO2Ph group in an efficient and regioselective reaction through C-H bond functionalization with a broad substrate scope in good to excellent yields.

Uses

Iododifluoromethyl phenyl sulfone can be used for the difluoromethylation of alkenes and alkynes initiated by triethylborane/air or arenediazonium salt/titanium chloride in moderate to good yields.

Reactions

(1) Difluoromethylation of terminal alkenes and alkynes.

Synthesis

Difluoromethyl phenyl sulfone (192 mg, 1 mmol) and elemental iodine (508 mg, 4 mmol) were dissolved in DMF (4 mL) in a Schlenk flask under argon protection. The system was cooled to -30 °C and a solution of t-BuOK (448 mg, 4 mmol) in DMF (4 mL) was added slowly dropwise via syringe. The reaction temperature was maintained between -30 °C and -20 °C with continuous stirring for 1 h. The reaction progress was monitored by 19F NMR tracking. Upon completion of the reaction, the reaction was quenched by the addition of 1N HCl aqueous solution (5 mL) at -50 °C, followed by slow warming to room temperature. Saturated aqueous NaCl solution (10 mL) was added and the reaction mixture was extracted with ether (15 mL x 3). The organic phases were combined, dried with anhydrous MgSO4, filtered and concentrated under reduced pressure to remove the solvent. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=9:1) to afford the target product difluoroiodomethyl phenyl sulfone (294 mg, 92% yield), which is a colorless solid and turns red easily when exposed to light. The product characterization data were as follows: 1H NMR (500 MHz, CDCl3): δ 7.63 (t, J = 7.4 Hz, 2H), 7.79 (t, J = 7.4 Hz, 1H), 7.99 (d, J = 7.5 Hz, 2H); 13C NMR (125 MHz, CDCl3): δ 102.5 (t, J = 355 Hz), 128.1, 129.7, 131.3, 136.1; 19F NMR (470 MHz, CDCl3): δ -52.2; MS (EI, m/z): 318 (M+), 177, 142, 127; HRMS (EI): m/z calcd for C7H5F2IO2S (M+) 317.9023, found 317.9013. found 317.9013.

References

[1] GUO-JIE YIN; W. F; Mei Zhu. Visible-light mediated regioselective (phenylsulfonyl)difluoromethylation of fused imidazoles with iododifluoromethyl phenyl sulfone[J]. Heterocyclic Communications, 2017. DOI:10.1515/hc-2017-0101.
[2] YA LI. Radical (Phenylsulfonyl)difluoromethylation with Iododifluoromethyl Phenyl Sulfone[J]. The Journal of Organic Chemistry, 2007. DOI:10.1021/jo070618s.