Environmental properties of pentafluorosulfanyl compounds: Physical properties and photodegradation

Abstract

The pentafluorosulfanyl (SF5) functional group was investigated from an environmental perspective to ascertain its physical properties and photolytic fate. Five aromatic probe compounds were compared with their trifluoromethyl analogs. Water solubilities for SF5 compounds ranged from 78 mg/L to 2.4 g/L. Octanol-water partitioning coefficients ranged from log K(OW) = 2.9 to 3.6, all of which were approximately 0.5 to 0.6 log units more hydrophobic than their trifluoromethyl analogs. The direct photolytic fate of SF5 compounds was studied, and the SF5 group was found to completely degrade using actinic radiation with hourly half-lives. The reaction was followed by high-performance liquid chromatography with a UV-visible detector, 19F nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry. It was found that five equivalents of fluoride were released to form a benzenesulfonate as a final product of photodegradation. Finally, an SF5 analog of fluometuron, a potentially new herbicide, was synthesized and likewise photolyzed. The present study provides the first evidence that pentafluorosulfanyl can degrade under mild, environmentally relevant conditions.

Synergistic Effects of Lewis Bases and Substituents on the Electronic Structure and Reactivity of Boryl Radicals

“…v) In CF 3 COOH (TFAH): Diazonium salt 1 (29.7 mg, 0.0934 mmol) was dissolved in TFAH (0.96 g) and the mixture was heated with 70 °C for 12 h. After cooling, a portion of the mixture was diluted with CDCl 3 and analyzed by NMR which indicated the formation of 1‐fluoro‐4‐(pentafluorosulfanyl)benzene,7 1‐fluoro‐4‐(fluorosulfonyl)benzene,23 4‐(pentafluorosulfanyl)phenol,9a and 4‐(fluorosulfonyl)phenol 24,25. Most of the solvent was evaporated to give a pale yellow oil, which was purified by SiO 2 column chromatography with hexane/EtOAc (9:1) to afford: 4‐(pentafluorosulfanyl)phenol, 4‐(fluorosulfonyl)phenol (colorless oil; 3.5 mg), and 4‐(fluorosulfonyl)phenol (colorless oil; 2.4 mg, 15 %).…”

Photoredox Catalytic α‐Alkoxypentafluorosulfanylation of α‐Methyl‐ and α‐Phenylstyrene Using SF6

“…For example, exchange of the widely used CF 3 substituent that is bioisosteric to CH 3 with a SF 5 substituent in the anoretic norfenfluramine induces a dramatic change in the pharmacological profile . Further evidence for a benign profile of organic SF 5 compounds has been reported . These features predict great potential for this functional group in chemistry .…”

Blue-to-Green Emitting Neutral Ir(III) Complexes Bearing Pentafluorosulfanyl Groups: A Combined Experimental and Theoretical Study

“…The −SF 5 group is strongly electron-withdrawing and has been shown to be lipophilic, thermally and chemically stable, and also biologically active. 33−35 However, despite these favorable properties, as yet it is an underexplored moiety in the field of organic semiconductor materials. 26 Nevertheless, these properties make the −SF 5 group an attractive candidate for replacing the commonly used C(aryl)–F motif, serving the same purpose of modulating the HOMO energy but without affecting the stability of the emitter.…”