Methanethiol
CH4S, 48.11 g/mol. Its structure, the values that were measured, the values that were calculated, and where each one came from.
Identifiers
- Molecular formula
- CH₄S
- Molecular weight
- 48.11 g/mol
- Exact mass
- 48.003371 g/mol
- IUPAC name
- methanethiol
- CS
- InChI=1S/CH4S/c1-2/h2H,1H3
- LSDPWZHWYPCBBB-UHFFFAOYSA-N
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
- 42.7 °F at 760 mmHg (EPA, 1998)
- 5.95 °C at 760 mm Hg
- Melting Point
- -189.4 °F (EPA, 1998)
- -123 °C
- Density
- 0.892 at 42.8 °F (USCG, 1999) - Less dense than water; will float
- 0.9600 at 25 °C/4 °C
- Solubility
- 2 % (NIOSH, 2024)
- Soluble in alcohol and ether; slightly soluble in chloroform
- Vapor Pressure
- 1 to 400 mmHg at -131.26 to 44.24 °F (EPA, 1998)
- 1,510 mm Hg at 25 °C
- Flash Point
- 0 °F (EPA, 1998)
- -18 °C
- Refractive Index
- 1.430-1.436 (gas); 0.894 (liquid)
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
- 48.11 g/mol
- Exact mass
- 48.0033713 Da
- XLogP3
- 0.5
- Polar surface area
- 1 Ų
- Complexity
- 2
- H-bond donors
- 1
- H-bond acceptors
- 1
- logP
- 0.546
- Topological polar surface area
- 0 Ų
- H-bond donors
- 1
- H-bond acceptors
- 1
- Rotatable bonds
- 0
- Molar refractivity
- 14.91 cm³/mol
- Fraction sp³ carbons
- 1
- QED drug-likeness
- 0.3795
What it is made of
Elements
Structure
- Heavy atoms, hydrogen excluded
- 2
- Total atoms, hydrogen included
- 6
- Rings
- 0
- Aromatic rings
- 0
- Stereocentres
- 0
- Formal charge
- 0
Functional groups
Thiol
The molecule in three dimensions
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
Other names for it
The systematic name on this record is methanethiol.
The sources also call it METHYL MERCAPTAN, Methylmercaptan, Mercaptomethane, Thiomethanol, Thiomethyl alcohol, Methvtiolo, Metilmercaptano, Methylmercaptaan, Mercaptan methylique, Methaanthiol, RCRA waste number U153.
Structurally related
Seen alongside it in reaction records
Molecules that appear in the same recorded reactions as Methanethiol. This says nothing about structure: most of them are the bases, solvents, ligands and catalysts the chemistry needed, and they are here because somebody put them in the same flask.
(Chloro-phenylmethyl)sulfinylbenzene
used as a reactant
C₁₃H₁₁ClOS, 250.75 g/mol.
(alpha-Methylthiobenzyl) phenyl sulfoxide
formed as a product
C₁₄H₁₄OS₂, 262.399 g/mol.
1,2,3,4-Tetrahydroisoquinolin-4-ol
used as a reactant
C₉H₁₁NO, 149.193 g/mol.
(4-Fluorophenyl)-[1-[2-[(1-methylsulfanyl-2-nitroethenyl)amino]ethyl]piperidin-4-yl]methanone
used as a reactant
C₁₇H₂₂FN₃O₃S, 367.446 g/mol.
(4-Fluorophenyl)-[1-[2-[[1-(methylamino)-2-nitroethenyl]amino]ethyl]piperidin-4-yl]methanone
formed as a product
C₁₇H₂₃FN₄O₃, 350.394 g/mol.
Where these values came from
chemistry engine
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.