Isophorone diisocyanate

Chembox new
Name = Isophorone diisocyanate
ImageFile = Isophorone-diisocyanate-2D-skeletal.png ImageName = Isophorone diisocyanate
ImageFile1 = Isophorone-diisocyanate-3D-vdW.png ImageName1 = Isophorone diisocyanate
IUPACName = 5-isocyanato-1-
(isocyanatomethyl)-
1,3,3-trimethyl-cyclohexane
OtherNames = IPDI
Section1 = Chembox Identifiers
SMILES = C1(C)(CN=C=O)CC(C)(C)CC(N=C=O)C1
CASNo = 4098-71-9
RTECS =
Section2 = Chembox Properties
Formula = C₁₂H₁₈N₂O₂
MolarMass = 222.3 g/mol
Appearance = Colourless liquid
Density = 1.062 g/cm³ @ 20 °C, liquid
Solubility =
MeltingPt = -60 °C (213 K)
BoilingPt = 158 °C (431 K) @ 1.33 kPa
pKa =
pKb =
Viscosity =
Section7 = Chembox Hazards
ExternalMSDS =
MainHazards =
FlashPt = 155°C (PMCC)
RPhrases =
SPhrases =
Section8 = Chembox Related
OtherAnions =
OtherCations =
Function = isocyanates
OtherFunctn = Hexamethylene diisocyanate
OtherCpds =

Isophorone diisocyanate (IPDI) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is produced in relatively small quantities, accounting for (with hexamethylene diisocyanate) only 3.4% of the global diisocyanate market in the year 2000.cite book | first=David | last=Randall | coauthors=Lee, Steve | title=The Polyurethanes Book | publisher=Wiley | location=New York | year=2002 | id=ISBN 0-470-85041-8] Aliphatic diisocyanates are used, not in the production of polyurethane foam, but in special applications, such as enamel coatings which are resistant to abrasion and degradation from ultraviolet light. These properties are particularly desirable in, for instance, the exterior paint applied to aircraft.

ynthesis

There are five steps to the synthesis of pure IPDI:
* "Condensation:" Conversion of acetone with a catalyst to produce isophorone
* "Hydrocyanation:" Reaction of the isophorone with hydrogen cyanide to form isophorone nitrile
* "Reductive amination:" Reaction of the isophorone nitrile with ammonia, hydrogen and a catalyst, to form a mixture of isophorone diamine conformers (25/75 cis/trans)
* "Phosgenation:" Reaction of the isophorone diamine with phosgene to form a crude mixture containing IPDI conformers (25/75 cis/trans)
* "Purification:" Distillation of the crude IPDI to extract pure IPDI

Chemistry

IPDI exists in two conformers, cis and trans. Their reactivities are similar. Each conformer is an asymmetrical molecule, and thus has isocyanate groups with different reactivities. The secondary isocyanate group is more reactive than the primary isocyanate group.

ee also

* Methylene diphenyl diisocyanate
* Toluene diisocyanate
* Isophorone

References

External links

* [http://www.cdc.gov/niosh/topics/isocyanates/ NIOSH Safety and Health Topic: Isocyanates] , from the website of the National Institute for Occupational Safety and Health (NIOSH)