Committed to preserving our shared environment – further details available on request.
Can be used in processes in compliance with cGMP standards.
Manufacture of consumables is accredited by the world renowned British Standards Institute.
Flexible supply chains, back up manufacturing and warehousing ensures supply risk reduction
Can be used in processes in compliance with GLP standards.
Products which are scaleable from lab or development to process scale.
Long to indefinite product shelf life, reduced process risk.
Supports pharma guidelines for reducing elemental impurities in APIs.
Further extractable information provided on request.
Raw materials certified free of materials of human or animal origin.
Chemical substances used in our manufacturing process do not require registration.
Able to withstand mechanical stirring and heating under normal reaction conditions.
Download the product note.
PS-Carbodiimide is a neutral, bound carbodiimide that can be used for the synthesis of amides and esters. The carbodiimide loading capacity is determined by 1H NMR (generation of Ac2O from AcOH in CDCl3). Amide formation may be conducted either without HOBt (Methods A), or with HOBt (Method B).
Excess HOBt can be scavenged after the reaction using MP-Carbonate Biotage® PS-Carbodiimide has been found to give superior results in comparison with N-Cyclohexylcarbodiimide-NI-Me PS resin and the quaternary carbodiimide resin P-EDC (Scheme 1, Table 1, click to enlarge table).
In general, PS-Carbodiimide was found to synthesize amides in high yield and purity without evidence of residual amine or carboxylic acid. Unreacted carboxylic acid, normally used in excess relative to the amine, remains bound to the resin during workup. PS-Carbodiimide may also be used for the synthesis of pentafluorophenyl (PFP) activated esters (Table 3, click to enlarge) and N-hydroxysuccinimidyl esters.
PS-Carbodiimide is very stable and lost less than 5% of its initial activity when stored at 4 ˚C for 2 years. This stability is due mostly to increased stabilization provided by the other linkage. Unlike other inferior copies, the carbodiimide moiety in Biotage PS-Carbodiimide is not Benzylic by deisgn.
Amine (1.0 equivalent) and acid (1.5 equivalent) in DCM (with 10% DMF added if necessary) was added to a dry reaction vessel and the mixture stirred for 10 min prior to addition of PS-Carbodiimide resin (2 equivalents) with a reaction solvent volume of 10 mL/g resin. The reaction was then stirred overnight.
PS-Carbodiimide (2.0 equivalents), acid (1.5 equivalent), and HOBt (1.7 equivalent) were dissolved in DCM, added to a dry reaction vessel and stirred for 5–10 min prior to addition of amine (1.0 equivalent). The reaction was stirred at room temperature overnight. After the reaction, the HOBt was scavenged using MP-Carbonate or PS-Trisamine resin (5 equivalents) for 2 h at room temperature prior to filtration.
General Procedure for Reaction Work-up
The reaction mixture is filtered and the amide product is collected in the filtrate. The resin is washed two times with the reaction solvent (DCM or DCM/DMF as needed for solubility). A sample from the combined fractions is generally analyzed by GC before concentration to evaluate product purity and presence (if any) of unreacted amine. Concentration affords the amide product in high yield.
Pentafluorophenyl Ester Formation
PS-Carbodiimide resin (1.6 equivalent) was added to a dry reaction vessel. The acid (1.3 equivalent) in DMF or DCM was added to the dry resin and the mixture stirred at room temperature for 5 min, followed by addition of PFP (1.0 equivalent). After 18 hrs at room temperature, the activated ester product was isolated from the resin by washing twice with DCM or DMF. HPLC analysis of activated esters show purities ranging from 89–98% (Table 2, click to enlarge).