Names | |
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IUPAC name
N,N'-dicyclohexylcarbodiimide
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Other names
DCC
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Identifiers | |
3D model (JSmol)
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ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.007.914 |
PubChem CID
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RTECS number | FF2160000 |
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Properties | |
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) |
not soluble | |
Hazards | |
R-phrases (outdated) | R22 R24 R41 R43 |
S-phrases (outdated) | S24 S26 S37/39 S45 |
NFPA 704 | |
Flash point | 113 °C (235 °F; 386 K) |
Related compounds | |
Related carbodiimides
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DIC,EDC |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
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, DCCD or DCCI.
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.