Hexamethyldisilazane

C6H19NSi2, 161.397 g/mol. Its structure, the values that were measured, the values that were calculated, and where each one came from.

verified recordOrganic compound8 measured properties

Drawn from the SMILES. It shows how the atoms are connected — not a photograph of a molecule, and not its shape in space.

Identifiers

Molecular formula: C₆H₁₉NSi₂
Molecular weight: 161.397 g/mol
Exact mass: 161.105603 g/mol
IUPAC name: [dimethyl-(trimethylsilylamino)silyl]methane
SMILES: C[Si](C)(C)N[Si](C)(C)C
InChI: InChI=1S/C6H19NSi2/c1-8(2,3)7-9(4,5)6/h7H,1-6H3
InChIKey: FFUAGWLWBBFQJT-UHFFFAOYSA-N

Open in ReactionLens Use in reaction prediction

Both are open without an account.

Measured properties

Values somebody obtained from a sample and published. Where two sources report the same property they are both shown, in the units each used — a disagreement between them is information, and averaging it away would be inventing a number neither one gave.

Boiling Point: 125 °Cmeasured · Lide, DR (ed.). CRC Handbook of Chemistry and Physics. 81st Edition. CRC Press LLC, Boca Raton: FL 2000, p. 3-311; 125 °C @760 [mm Hg]measured · reference compound database
Flash Point: 48 °F (NFPA, 2010)measured · National Fire Protection Association. 2010. Fire Protection Guide to Hazardous Materials, 14th edition, edited by Guy R. Colonna. Quincy, MA: National Fire Protection Association. Note that this information is subject to the copyright restrictions of the organization that provided the data.; 27 °Cmeasured · reference compound database; 81 °F (27 °C) closed cupmeasured · O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 837; 14 °C (closed cup) /from table/measured · Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990, p. 1848
Solubility: Soluble in acetone, benzene, ethyl ether, heptane, perchloroethylenemeasured · Lewis, R.J., Sr (Ed.). Hawley's Condensed Chemical Dictionary. 13th ed. New York, NY: John Wiley & Sons, Inc. 1997., p. 573; Insol in water, reacts slowlymeasured · O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 837; In water, 392 mg/l @ 25 °C /Estimated/measured · US EPA; Estimation Program Interface (EPI) Suite. Ver.3.11. June 10, 2003. Available from, as of Feb 25, 2004: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
Density: 0.7741 g/cu cm at 25 °Cmeasured · Lide, DR (ed.). CRC Handbook of Chemistry and Physics. 81st Edition. CRC Press LLC, Boca Raton: FL 2000, p. 3-311; 0.76 @25 °Cmeasured · reference compound database
Vapor Pressure: 13.8 [mmHg]measured · reference compound database; 13.8 mm Hg at 25 °Cmeasured · Yaws CL; Handbook of Vapor Pressure. Volume 2 - C5 to C7 Compounds. Houston TX: Gulf Pub Co pp. 391 (1994); 13.8 [mm Hg] @25 °Cmeasured · reference compound database
LogP: log Kow = 2.62 /Estimated/measured · US EPA; Estimation Program Interface (EPI) Suite. Ver.3.11. June 10, 2003. Available from, as of Feb 25, 2004: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
Viscosity: 0.90 centistokesmeasured · O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 837
Refractive Index: Index of refraction = 1.4090 @ 20 °Cmeasured · Lide, DR (ed.). CRC Handbook of Chemistry and Physics. 81st Edition. CRC Press LLC, Boca Raton: FL 2000, p. 3-311

Calculated properties

Derived from the structure rather than from a sample. These are reproducible and they are not measurements: a calculated partition coefficient and a measured one can differ by a long way, and where both exist they are listed apart on purpose.

Molecular weight: 161.39 g/molcalculated · reference compound database; Average mass of one molecule, from reference compound database.
Exact mass: 161.10560268 Dacalculated · reference compound database; Mass of the most common isotopic form.
Polar surface area: 12 Å²calculated · reference compound database; Polar surface area as computed by reference compound database.
Complexity: 76calculated · reference compound database; A rough measure of how intricate the structure is.
H-bond donors: 1calculated · reference compound database
H-bond acceptors: 1calculated · reference compound database
logP: 2.2458calculated · chemistry engine; Estimated preference for oil over water. Higher means more oil-like.
Topological polar surface area: 12.03 Å²calculated · chemistry engine; Surface area from polar atoms; relates to how easily a molecule crosses membranes.
H-bond donors: 1calculated · chemistry engine; Atoms that can donate a hydrogen bond.
H-bond acceptors: 1calculated · chemistry engine; Atoms that can accept a hydrogen bond.
Rotatable bonds: 2calculated · chemistry engine; Single bonds the molecule can freely twist around.
Molar refractivity: 49.8277 cm³/molcalculated · chemistry engine; Relates to the molecule's polarisability.
Fraction sp³ carbons: 1calculated · chemistry engine; Share of carbon atoms with tetrahedral bonding.
QED drug-likeness: 0.6126calculated · chemistry engine; Quantitative estimate of drug-likeness (0–1).

What it is made of

Elements

C Carbon6 atoms · 44.7% by mass
Si Silicon2 atoms · 34.8% by mass
H Hydrogen19 atoms · 11.9% by mass
N Nitrogen1 atom · 8.7% by mass

Percentages are of the molecular weight above, worked out the same way the molar mass calculator does it.

Structure

Heavy atoms, hydrogen excluded: 9
Total atoms, hydrogen included: 28
Rings: 0
Aromatic rings: 0
Stereocentres: 0
Formal charge: 0

The molecule in three dimensions

Rotate and inspect the atoms. Loaded only when you ask, so the page stays light.

The drawing above is a diagram of what is bonded to what. A molecule is not flat, and the model here is one low-energy shape generated from the connectivity — useful for seeing which groups can reach each other, and not a measured structure. A real sample is a population of conformations, interconverting.

Reactions it appears in

No documented reaction with a written procedure and a source involves Hexamethyldisilazane yet.

Other names for it

The systematic name on this record is [dimethyl-(trimethylsilylamino)silyl]methane.

The sources also call it HMDS, Bis(trimethylsilyl)amine, 1,1,1,3,3,3-Hexamethyldisilazane, Hexamethylsilazane, 1,1,1-Trimethyl-N-(trimethylsilyl)silanamine, Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, TSL 8802, hexamethyl disilazane, Disilazane, 1,1,1,3,3,3-hexamethyl-, SZ 6079, DTXSID2025395.

Structurally related

Nothing structurally close to Hexamethyldisilazane has a page here yet.

Where these values came from

reference compound database13838
compound record
chemistry engine
structure perception

compound record.

What this page does not claim

The identifiers are what the source record holds, copied rather than recomputed. Measured values are reported as their source gave them, units and all; calculated values are marked as calculated and are not measurements. Where a field is absent the page says so, because a blank cell reads as a zero and a guessed value reads as a fact.

Nothing here is a hazard assessment, a purity statement or advice about handling a sample. A flash point quoted from a safety database is a number somebody published, not a judgement by us about whether this molecule is safe for what you intend.