Flash vacuum pyrolysis studies. 9. Photoelectron spectra and molecular properties. 101. Synthesis and thermal decomposition of 1,3-dithietane and its S-oxides

A Formal Carbon–Sulfur Triple Bond: HCSOH

“…1,3-Dithietan-1,3-dioxide (5) was prepared according a procedure reported by Block et al [8] The precursor bis(chloromethyl) sulfoxide was prepared based on the procedure described by Venier et al using thionyl chloride and diazomethane. [20] [D 4 ]-1,3-Dithietan-1,3-dioxide was obtained by carrying out the following procedure twice: dissolving the parent compound in a large excess of slightly alkaline D 2 O, keeping the solution for 2 h at 70 8C, and evaporating the solvent under reduced pressure at 0 8C.…”

“…potential energy surface (PES) Figure 2) through the generation and photochemical rearrangement of thioformaldehyde S-oxide (H 2 C = S = O (6), Scheme 1), generated thermally by high-vacuum flash pyrolysis (HVFP) from its dimer 5. Although structure 6 has been characterized spectroscopically, [7,8] we report the UV spectrum of this parent compound for the first time (see the Supporting Information). The absorption maximum at 243 nm is well reproduced computationally (240 nm at TD-B3LYP/6-311 + G(3df,3pd)) and can be assigned to a p-p* transition.…”

“…Photolysis of 6 in an argon matrix with a broad-band light source (l > 300 nm) only led to unspecific decomposition to CO, COS, and ethylene. [7,8] As the choice of the excitation wavelength turned out to be critical, we repeated the matrix photolysis of 6 and its deuterated isotopologue [D 2 ]6 monochromatic light sources and were thus able to induce specific rearrangement to 1 at l = 254 nm, which is close to the actual UV absorption maximum.…”

Thioformaldehyde single rotational level photophysics: Longer than radiative lifetimes and reduced fluorescence yields in the isolated molecule

“…Block et al 32 have reported the synthesis of the dimer ofthioformaldehyde (1, 3-dithietane) and shown that the only pyrolysis product detectable by photoelectron spectroscopy is thioformaldehyde. The process is reported to be quantitative at a temperature of 600 °C.…”

Synthesis, structure, and chemistry of selenium-containing four-membered rings

“…Adams has developed a useful approach to the synthesis of mesocyclic polyselenacycloalkanes such as 1,5,9-triselenacyclododecane using rhenium carbonyl complexes of 3,3-dimethylselenetane as catalysts [3f,g] We have previously synthesized and explored the chemistry of 4-and 6-membered rings containing two sulfur or selenium atoms, such as 1,3-dithietane, 1, and 1,2-dithiin, 1,2-diselenin, and 2-selenathiin, 2 [4][5][6][7] as well as the structure and coordination chemistry of small acyclic organoselenium compounds including dimethyl diselenide [8], dimethyl selenoxide [9], and dimethyl selenone [10]. We sought to extend these studies to other unknown or little studied heterocycles containing sulfur and/or selenium, particularly those containing the selenetane ring, whose coordination chemistry has been scarcely studied.…”