Direct fixation of [(11)C]-CO(2) by amines: formation of [(11)C-carbonyl]-methylcarbamates.
[(11)C-Carbonyl]-methylcarbamates can be synthesised directly from [(11)C]-CO(2) and primary or secondary amines in a one-pot, two-step reaction. The use of either diazabicyclo[5.4.0]undec-7-ene (DBU) or 2-tert-butylimino-2-diethylamino-1,3-dimethyl-perhydro-1,3,2-diazaphosphorine (BEMP) enables efficient trapping of [(11)C]-CO(2) in small volumes of DMF as [(11)C]-carbamate salts. Subsequent reaction with a variety of methylating agents rapidly generates the desired [(11)C-carbonyl]-methylcarbamates in high radiochemical yields. The usefulness of the method is illustrated by the efficient radiosynthesis of a kappa opioid receptor imaging radiotracer, useful in positron emission tomography (PET).
Wilson
Alan A
AA
PET Centre, Centre for Addiction and Mental Health and University of Toronto, Toronto, Canada. alan.wilson@camhpet.ca
Garcia
Armando
A
Houle
Sylvain
S
Vasdev
Neil
N
D000588:Amines / Q000737:chemistry*; D001643:Bridged Bicyclo Compounds / Q000737:chemistry; D002219:Carbamates / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry* / Q000302:isolation & purification*; D002250:Carbon Radioisotopes / Q000737:chemistry; D008745:Methylation; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals / Q000138:chemical synthesis
D000588:Amines; D001643:Bridged Bicyclo Compounds; D002219:Carbamates; D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D002245:Carbon Dioxide