Dimethylsilanediol

Dimethylsilanediol
Names
IUPAC name
Dihydroxy(dimethyl)silane[1]
Other names
  • 1,1-Dimethylsilanediol[1]
  • Dihydroxydimethylsilane[1]
  • Dimethyldihydroxysilane[1]
  • Dimethylsilanediol[1]
Identifiers
3D model (JSmol)
1731569
ChEBI
ChemSpider
ECHA InfoCard 100.012.651
EC Number
  • 213-915-7
404726
UNII
  • InChI=1S/C2H8O2Si/c1-5(2,3)4/h3-4H,1-2H3
    Key: XCLIHDJZGPCUBT-UHFFFAOYSA-N
  • C[Si](C)(O)O
Properties
(CH3)2Si(OH)2
Molar mass 92.169 g·mol−1
Appearance Colorless or white crystalline solid[2][3]
Density 1.097 g/cm3[2]
Melting point 101 °C (214 °F; 374 K)[2]
Highly soluble[4]
Solubility Slightly soluble in DMSO and methanol[2]
Structure
Tetrahedral at Si
Hazards
GHS labelling:
Warning
H361
P203, P280, P318, P405, P501
Related compounds
Related compounds
Trimethylsilanol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Dimethylsilanediol or DMSD is an organosilicon compound with the chemical formula (CH3)2Si(OH)2. It is a colorless crystalline solid. It belongs to the category of silanols. Molecule of dimethylsilanediol has tetrahedral molecular geometry, where two methyl and two hydroxyl groups are attached to the central silicon atom. Dimethylsilanediol is a silicon analog of unstable propane-2,2-diol (CH3)2C(OH)2, where the central C atom is replaced by Si atom.

Synthesis

Dimethylsilanediol is produced by hydrolysis of dichlorodimethylsilane.[5]

(CH3)2SiCl2 + 2 H2O → (CH3)2Si(OH)2 + 2 HCl

Dimethylsilanediol, while not sold commercially, has been demonstrated to be one of the degradation product of polydimethylsiloxane polymers and oligomers in the environment.[6][7]

Uses

It is a reaction intermediate in the synthesis of organosilicon compounds such as polydimethylsiloxane.[8]

Reactions and properties

Dimethylsilanediol readily polymerizes to give a mixture of polydimethylsiloxanes, primarily composed of the cyclomethicones octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6), but also containing a small amount of dimethiconol, the linear polymer.[9] It is hygroscopic and temperature sensitive. It should be kept under inert atmosphere.[2] Because it having two hydroxyl groups, it has ability to form hydrogen bonds, which enhances its solubility in polar solvents.[10]

References

  1. ^ a b c d e PubChem. "Dimethylsilanediol". pubchem.ncbi.nlm.nih.gov. Retrieved 23 March 2026.
  2. ^ a b c d e Chemical Book. "dimethylsilanediol". www.chemicalbook.com. Retrieved 24 March 2026.
  3. ^ Cella, James A.; Carpenter, John C. (October 18, 1994). "Procedures for the preparation of silanols". Journal of Organometallic Chemistry. 480 (1): 23–26. doi:10.1016/0022-328X(94)87098-5 – via ScienceDirect.
  4. ^ https://www.sigmaaldrich.com/GB/en/tech-docs/paper/1231615
  5. ^ "Silicone: Chemie und Technologie, Herstellung der Ausgangsmaterialien". daten.didaktikchemie.uni-bayreuth.de. Retrieved 25 March 2026.
  6. ^ Kim, Jaeshin; Xu, Shihe; Courtemanche, Marc-André (2025). "Modeling of dimethylsilanediol fate and transport in soil". Integrated Environmental Assessment and Management. pp. 1134–1147. doi:10.1093/inteam/vjaf072. PMID 40489648. Retrieved 25 March 2026.
  7. ^ Xu, Shihe; Courtemanche, Marc-André; Miller, Julie (March 1, 2024). "Fate of dimethylsilanediol (DMSD) in soil-plant systems". Chemosphere. 352 141454. doi:10.1016/j.chemosphere.2024.141454. PMID 38354863 – via ScienceDirect.
  8. ^ Fulem, Michal; Štejfa, Vojtěch; Růžička, Květoslav; Molnar, Michael (May 21, 2025). "Sublimation Pressure and Heat Capacity of Dimethylsilanediol". International Journal of Thermophysics. 46 (7): 99. doi:10.1007/s10765-025-03570-0 – via Springer Link.
  9. ^ Lasocki, Z.; Chrzczonowicz, S. (June 24, 1962). "Kinetics of the polycondensation of dimethylsilanediol". Journal of Polymer Science. 59 (168): 259–269. doi:10.1002/pol.1962.1205916804 – via CrossRef.
  10. ^ cymitquimica.com. "CAS 1066-42-8: dimethylsilanediol". cymitquimica.com. Retrieved 24 March 2026.