3-Hydroxy-3-methylbutanoic acid

  • b-Hydroxyisovaleric acid
  • 3-Hydroxyisovaleric acid
  • 3-Hydroxy-3-methylbutyric acid
  • b-Hydroxy-b-methylbutyric acid
Formula
C5H10O3
Structure
Description
Clear, viscous, faintly yellow-green liquid.

Registry Numbers and Inventories.
CAS
625-08-1
36/37/38
UN (DOT)
3334
Beilstein/Gmelin
1743952
Beilstein Reference
4-03-00-00827

Properties.
Formula
C5H10O3
Formula mass
118.13
Melting point, °C
-80
Boiling point, °C
243
Vapor pressure, mmHg
0.006 (25 C)
Critical temperature
401
Critical pressure
44.0
Density
0.9384 g/cm3 (20 C)
Solubility in water
295 g/L (25 C)
Refractive index
1.5081 (20<sup>o</sup>C)
pKa/pKb
4.38 (pKa)
Partition coefficient, pKow
-0.79
Heat of vaporization
55.75 kJ/mol

Hazards and Protection.
Storage
Keep tightly closed. Store in a cool dry place.
Protection
Compatible chemical-resistant gloves. Chemical safety goggles. Protective clothing.
Respirators
Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU). Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multi-purpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator.
Small spills/leaks
Cover with dry lime or soda ash, pick up, keep in a closed container, and hold for waste disposal. Ventilate area and wash spill site after material pickup is complete.
Incompatibilities
Strong oxidizing agents.
Decomposition
Oxides of carbon.

Fire.
Flash Point,°C
113
Fire fighting
Extinguish with water spray, carbon dioxide, dry chemical powder or appropriate foam. Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes.
Hazards
Emits toxic fumes under fire conditions.

Health.
Exposure effects
Vapor or mist is irritating to the eyes, mucous membranes, and upper respiratory tract. May be harmful by inhalation, ingestion, or skin absorption.
   Inhalation
Causes irritation.

First aid
 
   Ingestion
If swallowed, wash out mouth with water provided person is conscious. Call a physician.
   Inhalation
If inhaled, remove to fresh air. If not breathing give artificial respiration. If breathing is difficult, give oxygen.
   Skin
In case of contact, immediately wash skin with soap and copious amounts of water. Remove contaminated clothing and shoes. Call a physician.
   Eyes
In case of contact with eyes, flush with copious amounts of water for at least 15 minutes. Assure adequate flushing by separating the eyelids with fingers. Call a physician.

Transport.
UN number
3334
Response guide
Hazard class
9
Packing Group
III