Ueber Thianthren und Selenanthren, C₁₂H₈Se₂. II

Abstract

Thianthren und SeIenanthren, C1gHs Se2. 11. (Eingegangen am 26. Februar.) Zur Darstellung des Selenanthrens erhitzt man in einem zur Vacuumdestillation geeigneten Kijlbchen rnit angeschmolzener Vorlage j e 10 g Thianthrendisulfon, die man zuvor mit 5.7 g Selen sorgfaltig

Synthesis and Conformational Dynamics of Selenanthrene (Oxides): Establishing an Energetic Flexibility Index for Scaffolds

“…23 Previous reports included neither 4 or selenanthrene-5,5,10,10-tetroxide (5) (both containing a selenone moiety). 1,21,22 However, we found that 4 did form after treating 1 with 4 equiv of m-CPBA and heating for 48 h. We made a minor attempt to obtain 5 by reaction of 1 with 10 equiv of m-CPBA in refluxing 1,2dichloroethane for 72 h. The major product from this reaction remained as 4; however, a very downfield 1 H NMR resonance was observed at 8.84 ppm, which we attribute to the presence of 5; we postulate that 5 could be obtained more cleanly if a stronger oxidant was used. One such reagent is dioxirane; it is more nucleophilic than m-CPBA and thus would more easily oxidize the electrophilic selenoxide in 4.…”

“…All other inorganic reagents were purchased from Fisher Scientific and used as received. 1 H, 13 C (101 MHz) and 77 Se NMR (76 MHz) spectra were collected on a Varian DirecDrive instrument equipped with a 400 MHz OneNMR 5 mm probe. Variable temperature NMR spectra were collected on a Varian Oxford 600 MHz instrument equipped with a 600 MHz OneNMR 5 mm probe.…”

“…The resulting solid was purified via column chromatography in isocratic DCM to afford 2 as a white powder (0.461 g, 44%). 1 H NMR (600 MHz, CD 2 Cl 2 ) δ: 7.91 (dd, J = 7.8, 1.4 Hz, 1H), 7.82 (dd, J = 7.6, 1.2 Hz, 1H), 7.57 (td, J = 7.6, 1.2 Hz, 1H), 7.43 (td, J = 7.5, 1.4 Hz, 1H). 13 -3).…”

“…The aqueous phase was extracted with a 15% isopropanol/DCM solution (3× 15 mL), and the organic layer was then dried over sodium sulfate and evaporated to afford 4 as a white powder (0.164 g, 48%). 1 H NMR (600 MHz, DMSO-d 6 ): δ 8.15 (dd, J = 7.6, 1.3 Hz, 2H), 7.96 (td, J = 7.6, 1.3 Hz, 1H), 7.87 (td, J = 7.6, 1.3 Hz, 1H). 13 C NMR (101 MHz, CDCl 3 ) δ: 145.60, 138.…”

“…a Unless otherwise noted, reactions were performed on the 1 mmol scale relative to 1,2-diiodobenzene at a concentration of 0.5 M. Conversions were determined by1 H NMR. b Isolated yield, >10 mmol scale.…”