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Names | |||
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IUPAC name
Propionaldehyde
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Preferred IUPAC name
Propanal | |||
Other names
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Identifiers | |||
3D model (
JSmol)
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3DMet | |||
ChEBI | |||
ChEMBL | |||
ChemSpider | |||
ECHA InfoCard | 100.004.204 | ||
EC Number |
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KEGG | |||
PubChem
CID
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RTECS number |
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UNII | |||
UN number | 1275 | ||
CompTox Dashboard (
EPA)
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Properties | |||
C3H6O | |||
Molar mass | 58.080 g·mol−1 | ||
Appearance | Colourless liquid | ||
Odor | Pungent and fruity | ||
Density | 0.81 g cm−3 | ||
Melting point | −81 °C (−114 °F; 192 K) | ||
Boiling point | 46 to 50 °C (115 to 122 °F; 319 to 323 K) | ||
20 g/100 mL | |||
-34.32·10−6 cm3/mol | |||
Viscosity | 0.6 cP at 20 °C | ||
Structure | |||
C1, O: sp2
C2, C3: sp3 | |||
2.52 D | |||
Hazards | |||
GHS labelling: | |||
Danger | |||
H225, H302, H315, H318, H332, H335 [1] | |||
P210, P261, P280, P304+P340+P312, P305+P351+P338, P310, P403+P235 [1] | |||
NFPA 704 (fire diamond) | |||
Flash point | −26 °C (−15 °F; 247 K) | ||
175 °C (347 °F; 448 K) | |||
Related compounds | |||
Related
aldehydes
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Acetaldehyde Butyraldehyde | ||
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
Propionaldehyde or propanal is the organic compound with the formula CH3CH2CHO. It is the 3-carbon aldehyde. It is a colourless, flammable liquid with a pungent and fruity odour. It is produced on a large scale industrially.
Propionaldehyde is mainly produced industrially by hydroformylation of ethylene:
In this way, several hundred thousand tons are produced annually. [2]
Propionaldehyde may also be prepared by oxidizing 1-propanol with a mixture of sulfuric acid and potassium dichromate. The reflux condenser contains water heated at 60 °C, which condenses unreacted propanol, but allows propionaldehyde to pass. The propionaldehyde vapor is immediately condensed into a suitable receiver. In this arrangement, any propionaldehyde formed is immediately removed from the reactor, thus it does not get over-oxidized to propionic acid. [3]
Propionaldehyde exhibits the reactions characteristic of alkyl aldehydes, e.g. hydrogenation, aldol condensations, oxidations, etc. It is the simplest aldehyde with a prochiral methylene such that α-functionalized derivatives (CH3CH(X)CHO) are chiral. If water is available, propionaldehyde exists in equilibrium with 1,1-propanediol, a geminal diol.
It is predominantly used as a precursor to trimethylolethane (CH3C(CH2OH)3) through a condensation reaction with formaldehyde. This triol is an important intermediate in the production of alkyd resins. It is used in the synthesis of several common aroma compounds ( cyclamen aldehyde, helional, lilial). Other applications include reduction to propanol and oxidation to propionic acid. [2]
Propionaldehyde is a common reagent, being a building block to many compounds. [4] Many of these uses exploit its participation in condensation reactions. [5][ verification needed] With tert-butylamine it gives CH3CH2CH=N-t-Bu, a three-carbon building block used in organic synthesis. [6]
Propionaldehyde along with acrolein has been detected in the molecular cloud Sagittarius B2 near the center of the Milky Way Galaxy, about 26,000 light years from Earth. [7] [8] [9]
Measurements by the COSAC and Ptolemy instruments on comet 67/P's surface, revealed sixteen organic compounds, four of which were seen for the first time on a comet, including acetamide, acetone, methyl isocyanate and propionaldehyde. [10] [11] [12]
With an LD50 of 1690 mg/kg (oral), [2] propionaldehyde exhibits low acute toxicity, but is a lung and eye irritant and is a combustible liquid.