N,N'-Dicyclohexylcarbodiimide

N,N'-Dicyclohexylcarbodiimide

Names
IUPAC name N,N'-dicyclohexylcarbodiimide
Other names DCC
Identifiers
CAS Number	538-75-0
3D model (Jmol)	Interactive image
ChEBI	CHEBI:53090
ChemSpider	10408 Y
ECHA InfoCard	100.007.914
PubChem CID	10868
RTECS number	FF2160000
InChI InChI=1S/C13H22N2/c1-3-7-12(8-4-1)14-11-15-13-9-5-2-6-10-13/h12-13H,1-10H2 Y Key: QOSSAOTZNIDXMA-UHFFFAOYSA-N Y InChI=1/C13H22N2/c1-3-7-12(8-4-1)14-11-15-13-9-5-2-6-10-13/h12-13H,1-10H2 Key: QOSSAOTZNIDXMA-UHFFFAOYAO
SMILES N(=C=N\C1CCCCC1)\C2CCCCC2
Properties
Chemical formula	C13H22N2
Molar mass	206.33 g·mol−1
Appearance	white crystalline powder
Density	1.325 g/cm3, solid
Melting point	34 °C (93 °F; 307 K)
Boiling point	122 °C (252 °F; 395 K) (at 6 mmHg)
Solubility in water	not soluble
Hazards
R-phrases	R22 R24 R41 R43
S-phrases	S24 S26 S37/39 S45
NFPA 704	1 3
Flash point	113 °C (235 °F; 386 K)
Related compounds
Related carbodiimides	DIC,EDC
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

N,N'-Dicyclohexylcarbodiimide is an organic compound with the chemical formula C₁₃H₂₂N₂ whose primary use is to couple amino acids during artificial peptide synthesis. Under standard conditions, it exists in the form of white crystals with a heavy, sweet odor. The low melting point of this material allows it to be melted for easy handling. It is highly soluble in dichloromethane, tetrahydrofuran, acetonitrile and dimethylformamide, but insoluble in water. The compound is often abbreviated as DCC or DCCD.

The C-N=C=N-C core of carbodiimides (N=C=N) is linear, being related to the structure of allene. Three principal resonance structures describe carbodiimides:

The N=C=N moiety gives characteristic IR spectroscopic signature at 2117 cm⁻¹. The ¹⁵N NMR spectrum shows a characteristic shift of 275.0 ppm upfield of nitric acid and the ¹³C NMR spectrum features a peak at about 139 ppm downfield from TMS.

Of the several syntheses of DCC, Pri-Bara et al. use palladium acetate, iodine, and oxygen to couple cyclohexyl amine and cyclohexyl isocyanide. Yields of up to 67% have been achieved using this route:

Tang et al. condense two isocyanates using the catalyst OP(MeNCH₂CH₂)₃N in yields of 92%:

DCC has also been prepared from dicyclohexylurea using a phase transfer catalyst by Jaszay et al. The disubstituted urea, arenesulfonyl chloride, and potassium carbonate react in toluene in the presence of benzyl tetraethylammonium chloride to give DCC in 50% yield.

DCC is a dehydrating agent for the preparation of amides, ketones, nitriles. In these reactions, DCC hydrates to form dicyclohexylurea (DCU), a compound that is nearly insoluble in most organic solvents and insoluble in water. The majority of the DCU is thus readily removed by filtration, although the last traces can be difficult to eliminate from non-polar products. DCC can also be used to invert secondary alcohols.