Chemistry:Triphenylamine

Triphenylamine

Names
Preferred IUPAC name N,N-Diphenylaniline
Other names Triphenylamine N,N,N-Triphenylamine N,N-Diphenylbenzeneamine
Identifiers
CAS Number	603-34-9 Y
3D model (JSmol)	Interactive image
ChemSpider	11282 Y
EC Number	210-035-5
PubChem CID	11775
RTECS number	YK2680000
UNII	NJS65M2DS2 Y
InChI InChI=1S/C18H15N/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15H Y Key: ODHXBMXNKOYIBV-UHFFFAOYSA-N Y InChI=1/C18H15N/c1-4-10-16(11-5-1)19(17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15H Key: ODHXBMXNKOYIBV-UHFFFAOYAF
SMILES c3c(N(c1ccccc1)c2ccccc2)cccc3
Properties
Chemical formula	C18H15N
Molar mass	245.32 g/mol
Appearance	Off-white solid
Density	0.774 g/cm3
Melting point	127 °C (261 °F; 400 K)
Boiling point	347 to 348 °C (657 to 658 °F; 620 to 621 K)
Solubility in water	Almost insoluble
log P	5.74
Hazards
GHS pictograms
GHS Signal word	Warning
GHS hazard statements	H315, H319
GHS precautionary statements	P264, P280, P302+352, P305+351+338, P321, P332+313, P337+313, P362
Flash point	180 °C (356 °F; 453 K) open cup
NIOSH (US health exposure limits):
PEL (Permissible)	none
REL (Recommended)	TWA 5 mg/m3
IDLH (Immediate danger)	N.D.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

Triphenylamine is an organic compound with formula (C₆H₅)₃N. In contrast to most amines, triphenylamine is nonbasic. At room temperature it appears as a colorless crystalline solid, with monoclinic structure. It is well miscible in diethyl ether and benzene, but it is practically insoluble in water, and partially in ethanol. Its derivatives have useful properties in electrical conductivity and electroluminescence, and they are used in OLEDs as hole-transporters.

Triphenylamine can be prepared by arylation of diphenylamine.

Chemical properties

Triphenylamine has three aromatic groups directly linked to the central nitrogen atom. Each aromatic group acts as an electron attractor, directing the electron cloud of the lone pair of nitrogen towards it. With the delocalization of the nitrogen lone pair, a partial positive charge is conferred to nitrogen, counterbalanced by the partial negative charge localized on the aromatic groups. This arrangement prevents nitrogen protonation, a key mechanism for providing basicity to a solution.

From this characteristic, moreover, it follows that the three N-C bonds all lie on the same plane and that they are located at 120° from each other, which is not the case with aliphatic amines and ammonia, where the orbitals of nitrogen are arranged in a tetrahedron. Due to steric hindrance, the phenyl groups are not on the same plane defined by the three N-C bonds, but are twisted, giving the molecule its characteristic "propeller-like" shape.

See also

• Triarylamine
• Triphenylphosphine

External links

• International Chemical Safety Card 1366
• SDS sheet at www.sigmaaldrich.com
• CDC - NIOSH Pocket Guide to Chemical Hazards
• Spectroscopy of triphenylamine (gas phase neutral, radical cation, protonated)