1,2-Diaminopropane

1,2-Diaminopropane (propane-1,2-diamine) is organic compound with the formula CH₃CH(NH₂)CH₂NH₂. A colorless liquid, it is the simplest chiral diamine. It is used as a bidentate ligand in coordination chemistry.

1,2-Diaminopropane

Names
Preferred IUPAC name Propane-1,2-diamine
Other names 1,2-Propanediamine
Identifiers
CAS Number	78-90-0 Y
3D model (JSmol)	Interactive image
Beilstein Reference	605274
ChEBI	CHEBI:30630 Y
ChemSpider	13849260 Y 394801 R N 557530 S N
ECHA InfoCard	100.001.051
EC Number	201-155-9
Gmelin Reference	25709
MeSH	1,2-diaminopropane
PubChem CID	6567 447820 R 642322 S
RTECS number	TX6650000
UNII	2A4P522UGO Y
UN number	2258
CompTox Dashboard (EPA)	DTXSID4021761
InChI InChI=1S/C3H10N2/c1-3(5)2-4/h3H,2,4-5H2,1H3 Y Key: dAOHJOMMDDJHIJH-UHFFFAOYSA-N N
SMILES CC(N)CN
Properties
Chemical formula	C3H10N2
Molar mass	74.127 g·mol−1
Appearance	Colourless liquid
Odor	Fishy, ammoniacal
Density	870 mg mL−1
Melting point	−37.1 °C; −34.9 °F; 236.0 K
Boiling point	119.6 °C; 247.2 °F; 392.7 K
Vapor pressure	1.9 kPa (at 20 °C)
Magnetic susceptibility (χ)	-58.1·10−6 cm3/mol
Refractive index (nD)	1.446
Thermochemistry
Heat capacity (C)	205.64 J K−1 mol−1
Std molar entropy (S⦵298)	247.27 J K−1 mol−1
Std enthalpy of formation (ΔfH⦵298)	−98.2–−97.4 kJ mol−1
Std enthalpy of combustion (ΔcH⦵298)	−2.5122–−2.5116 MJ mol−1
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H226, H302, H312, H314
Precautionary statements	P280, P305+P351+P338, P310
Flash point	34 °C (93 °F; 307 K)
Autoignition temperature	360 °C (680 °F; 633 K)
Explosive limits	1.9–11.1%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	434 mg kg−1 (dermal, rabbit) 2.23 g kg−1 (oral, rat)
Related compounds
Related alkanamines	Ethylamine Ethylenediamine Propylamine Isopropylamine 1,3-Diaminopropane Isobutylamine tert-Butylamine n-Butylamine sec-Butylamine Putrescine
Related compounds	2-Methyl-2-nitrosopropane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Preparation

Industrially, this compound is synthesized by the ammonolysis of 1,2-dichloropropane:^[1]

CH₃CHClCH₂Cl + 4 NH₃ → CH₃CH(NH₂)CH₂NH₂ + 2 NH₄Cl

This preparation allows for the use of waste chloro-organic compounds to form useful amines using inexpensive and readily available ammonia.^[1]

The racemic mixture of this chiral compound may be separated into enantiomers by conversion into the diastereomeric tartaric acid ammonium salt. After purification of the diastereomer, the diamine can be regenerated by treatment of the ammonium salt with sodium hydroxide.^[2] Alternate reagents for chiral resolution include N-p-toluenesulfonylaspartic acid, N-benzenesulfonylaspartic acid, or N-benzoylglutamic acid.^[3]

Uses

Metal deactivator

1,2-Diaminopropane is used in the synthesis of N,N′-disalicylidene-1,2-propanediamine, a salen-type ligand, usually abbreviated as salpn, that is used as a metal deactivating additive in motor oils.^[4]

Related compounds

/* Uses */ Two chiral 1,2-diamines are 1,2-diaminocyclohexane and 2,3-diaminobutane.

References

1. Bartkowiak, M.; Lewandowski, G.; Milchert, E.; Pelech, R. (2006). "Optimization of 1,2-Diaminopropane Preparation by the Ammonolysis of Waste 1,2-Dichloropropane". Ind. Eng. Chem. Res. 45 (16): 5681–5687. doi:10.1021/ie051134u.
2. Romanowski, G.; Wera, M. (2010). "Mononuclear and dinuclear chiral vanadium(V) complexes with tridentate Schiff bases derived from R(−)-1,2-diaminopropane: Synthesis, structure, characterization and catalytic properties". Polyhedron. 29 (13): 2747–2754. doi:10.1016/j.poly.2010.06.030.
3. JP application 04-018057, Sakie, N. & Haruyo, S., "Production of Optically Active 1,2-propanediamine"
4. Dabelstein, W.; Reglitzky A.; Schutze A.; Reders, K. "Automotive Fuels". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_719.pub2. ISBN 978-3527306732.