Thioformaldehyde Explained

Thioformaldehyde is the organosulfur compound with the formula CH₂S. It is the simplest thioaldehyde. This compound is not observed in the condensed state (solid or liquid) because it oligomerizes to 1,3,5-trithiane, which is a stable colorless compound with the same empirical formula.

Despite the instability of these concentrated forms, thioformaldehyde as a dilute gas has been extensively studied. For these purposes, it is produced by thermal decomposition of dimethyl disulfide.^[1] The molecule has been observed in the interstellar medium^[2] and has attracted much attention for its fundamental nature.^[3] The tendency of thioformaldehyde to form chains and rings is a manifestation of the double bond rule.

Although thioformaldehyde tends to oligomerize, many metal complexes are known. One example is Os(SCH₂)(CO)₂(PPh₃)₂.^[4]

References

1. 10.1016/0022-2852(71)90284-0 . Microwave spectrum, ground state structure, and dipole moment of thioformaldehyde . 1971 . Johnson . Donald R. . Powell . Francis X. . Kirchhoff . William H. . Journal of Molecular Spectroscopy . 39 . 136–145 . 1971JMoSp..39..136J .
2. Despois, D., "Radio Line Observations of Molecular and Isotopic Species in Comet C/1995 O1 (Hale-Bopp) Implications on the Interstellar Origin of Cometary Ices", Earth, Moon, Planets 1999, 79, 103-124.
3. 10.1146/annurev.pc.34.100183.000335. The Spectroscopy of Formaldehyde and Thioformaldehyde. 1983. Clouthier. D. J.. Ramsay. D. A.. Annual Review of Physical Chemistry. 34. 31–58. 1983ARPC...34...31C.
4. 10.1039/C0DT00975J. The coordination chemistry of small sulfur-containing molecules: A personal perspective. 2011. Schenk. Wolfdieter A.. Dalton Trans. 40. 6. 1209–1219. 21088787.