Isobutyric Acid

A carboxylic acid, C4H8O2, 88.106 g/mol. Boiling point 154.4 °C, melting point -46 °C, as published.

verified recordOrganic — carboxylic acid9 measured properties

Identifiers

Molecular formula: C₄H₈O₂
Molecular weight: 88.106 g/mol
Exact mass: 88.052429 g/mol
IUPAC name: 2-methylpropanoic acid
SMILES: CC(C)C(=O)O
InChI: InChI=1S/C4H8O2/c1-3(2)4(5)6/h3H,1-2H3,(H,5,6)
InChIKey: KQNPFQTWMSNSAP-UHFFFAOYSA-N

Open in ReactionLens Use in reaction prediction

Measured properties

Published measurements, each with its source. Two readings of one property are both shown, in the units each used.

Boiling Point: 309 °F at 760 mmHg (USCG, 1999)measured · CAMEO Chemicals; 154.4 °Cmeasured · DrugBank
Melting Point: -51 °F (USCG, 1999)measured · CAMEO Chemicals; -46 °Cmeasured · DrugBank
Density: 0.949 at 68 °F (USCG, 1999) - Less dense than water; will floatmeasured · CAMEO Chemicals; 0.950 at 20 °C/4 °Cmeasured · Hazardous Substances Data Bank (HSDB)
Solubility: 167000 mg/L (at 20 °C)measured · DrugBank; Slightly soluble in carbon tetrachloridemeasured · Hazardous Substances Data Bank (HSDB)
Vapor Pressure: 1.81 [mmHg]measured · Haz-Map, Information on Hazardous Chemicals and Occupational Diseases; 1.81 mm Hg at 25 °Cmeasured · Hazardous Substances Data Bank (HSDB)
LogP: 0.94measured · DrugBank; log Kow = 0.94measured · Hazardous Substances Data Bank (HSDB)
Flash Point: 132 °F (NFPA, 2010)measured · CAMEO Chemicals; 77 °Cmeasured · Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Viscosity: 1.126 mPa.smeasured · Lide, D.R. CRC Handbook of Chemistry and Physics 86TH Edition 2005-2006. CRC Press, Taylor & Francis, Boca Raton, FL 2005, p. 3-19
Refractive Index: Index of refraction: 1.3930 at 20 °C/Dmeasured · O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 2006., p. 892; 1.392-1.395measured · reference compound database

Calculated properties

Derived from the structure, not from a sample; kept apart from the measurements above.

Molecular weight: 88.11 g/molcalculated · reference compound database; Average mass of one molecule, from reference compound database.
Exact mass: 88.052429494 Dacalculated · reference compound database; Mass of the most common isotopic form.
XLogP3: 0.8calculated · reference compound database; Estimated oil/water partition, computed by reference compound database.
Polar surface area: 37.3 Å²calculated · reference compound database; Polar surface area as computed by reference compound database.
Complexity: 56calculated · reference compound database; A rough measure of how intricate the structure is.
H-bond donors: 1calculated · reference compound database
H-bond acceptors: 2calculated · reference compound database
logP: 0.727calculated · chemistry engine; Estimated preference for oil over water. Higher means more oil-like.
Topological polar surface area: 37.3 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: 1calculated · chemistry engine; Single bonds the molecule can freely twist around.
Molar refractivity: 22.4738 cm³/molcalculated · chemistry engine; Relates to the molecule's polarisability.
Fraction sp³ carbons: 0.75calculated · chemistry engine; Share of carbon atoms with tetrahedral bonding.
QED drug-likeness: 0.5126calculated · chemistry engine; Quantitative estimate of drug-likeness (0–1).

What it is made of

Elements

C Carbon4 atoms · 54.5% by mass
O Oxygen2 atoms · 36.3% by mass
H Hydrogen8 atoms · 9.2% 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: 6
Total atoms, hydrogen included: 14
Rings: 0
Aromatic rings: 0
Stereocentres: 0
Formal charge: 0

Functional groups

Carboxylic acid
A carbon double-bonded to oxygen and bonded to an –OH group; acidic.

Matched by structural pattern, not by a measurement.

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 Isobutyric Acid yet.

Other names for it

The systematic name on this record is 2-methylpropanoic acid.

The sources also call it 2-Methylpropanoic acid, Isobutanoic acid, Isopropylformic acid, Dimethylacetic acid, Iso-butyric acid, Propanoic acid, 2-methyl-, Cenex RP b2, alpha-Methylpropanoic acid, alpha-Methylpropionic acid, Acetic acid, dimethyl-, Propionic acid, 2-methyl-.

Structurally related

Molecules sharing this formula, or whose fingerprint is at least 40% similar to this one. Similarity is Tanimoto on Morgan fingerprints over this library only — it is a measure of structural overlap, not of how alike they behave.

1,3-Propanediol, 2-methylene-

C4H8O2

(+-)-2-Hydroxyisovaleric acid

C5H10O3

Seen alongside it in reaction records

Molecules that appear in the same recorded reactions as Isobutyric Acid. 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.

(((10-Bromodecyl)oxy)methyl)benzene

used as a reactant

C₁₇H₂₇BrO, 327.306 g/mol.

Where these values came from

reference compound database6590
compound record
chemistry engine
structure perception

compound record.

What this page does not claim

Identifiers are copied from the source record, measured values are reported as published, and calculated values are marked as calculated. Nothing here is a hazard, purity or handling assessment — how the library is checked.