Recent from talks
Carbonyldiimidazole
Knowledge base stats:
Talk channels stats:
Members stats:
Carbonyldiimidazole
1,1'-Carbonyldiimidazole (CDI) is an organic compound with the molecular formula (C3H3N2)2CO. It is a white crystalline solid. It is often used for the coupling of amino acids for peptide synthesis and as a reagent in organic synthesis.
CDI can be prepared straightforwardly by the reaction of phosgene with four equivalents of imidazole under anhydrous conditions. Removal of the side product, imidazolium chloride, and solvent results in the crystalline product in ~90% yield.
In this conversion, the imidazole serves both as the nucleophile and the base. An alternative precursor 1-(trimethylsilyl)imidazole requires more preparative effort with the advantage that the coproduct trimethylsilyl chloride is volatile.
CDI hydrolyzes readily to give back imidazole:
The purity of CDI can be determined by the amount of CO2 that is formed upon hydrolysis.
CDI is mainly employed to convert amines into amides, carbamates, ureas. It can also be used to convert alcohols into esters.
The formation of amide is promoted by CDI. Although the reactivity of CDI is less than acid chlorides, it is more easily handled and avoids the use of thionyl chloride in acid chloride formation, which can cause side reactions. An early application of this type of reaction was noted in the formation of peptide bonds (with CO2 formation as a driving force). The proposed mechanism for the reaction between a carboxylic acid and CDI is presented below.
In the realm of peptide synthesis, this product may be treated with an amine such as that found on an amino acid to release the imidazole group and couple the peptides. The side products, carbon dioxide and imidazole, are relatively innocuous. Racemization of the amino acids also tends to be minimal, reflecting the mild reaction conditions.
Hub AI
Carbonyldiimidazole AI simulator
(@Carbonyldiimidazole_simulator)
Carbonyldiimidazole
1,1'-Carbonyldiimidazole (CDI) is an organic compound with the molecular formula (C3H3N2)2CO. It is a white crystalline solid. It is often used for the coupling of amino acids for peptide synthesis and as a reagent in organic synthesis.
CDI can be prepared straightforwardly by the reaction of phosgene with four equivalents of imidazole under anhydrous conditions. Removal of the side product, imidazolium chloride, and solvent results in the crystalline product in ~90% yield.
In this conversion, the imidazole serves both as the nucleophile and the base. An alternative precursor 1-(trimethylsilyl)imidazole requires more preparative effort with the advantage that the coproduct trimethylsilyl chloride is volatile.
CDI hydrolyzes readily to give back imidazole:
The purity of CDI can be determined by the amount of CO2 that is formed upon hydrolysis.
CDI is mainly employed to convert amines into amides, carbamates, ureas. It can also be used to convert alcohols into esters.
The formation of amide is promoted by CDI. Although the reactivity of CDI is less than acid chlorides, it is more easily handled and avoids the use of thionyl chloride in acid chloride formation, which can cause side reactions. An early application of this type of reaction was noted in the formation of peptide bonds (with CO2 formation as a driving force). The proposed mechanism for the reaction between a carboxylic acid and CDI is presented below.
In the realm of peptide synthesis, this product may be treated with an amine such as that found on an amino acid to release the imidazole group and couple the peptides. The side products, carbon dioxide and imidazole, are relatively innocuous. Racemization of the amino acids also tends to be minimal, reflecting the mild reaction conditions.
Recent media