Synlett 2015; 26(16): 2257-2260
DOI: 10.1055/s-0034-1381055
letter
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 11C-Labelled Symmetrical Ureas via the Rapid Incorporation of [11C]CO2 into Aliphatic and Aromatic Amines

Abdul Karim Haji Dheere
Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor Lambeth Wing, London, SE1 7EH, UK   Email: antony.gee@kcl.ac.uk
,
Salvatore Bongarzone
Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor Lambeth Wing, London, SE1 7EH, UK   Email: antony.gee@kcl.ac.uk
,
Carlotta Taddei
Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor Lambeth Wing, London, SE1 7EH, UK   Email: antony.gee@kcl.ac.uk
,
Ran Yan
Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor Lambeth Wing, London, SE1 7EH, UK   Email: antony.gee@kcl.ac.uk
,
Antony D. Gee*
Division of Imaging Sciences and Biomedical Engineering, King’s College London, 4th Floor Lambeth Wing, London, SE1 7EH, UK   Email: antony.gee@kcl.ac.uk
› Author Affiliations
Further Information

Publication History

Received: 14 May 2015

Accepted after revision: 02 July 2015

Publication Date:
04 September 2015 (eFirst)

Abstract

An efficient method to radiolabel symmetrical [11C]ureas using 1,8-diazabicycloundec-7-ene (DBU) and cyclotron-produced [11C]CO2 has been developed. [11C]urea derivatives were obtained when aliphatic and aromatic amines were used with excellent radiochemical yields (RCYs) of over 70%. The mechanism of the reaction is proposed on the basis of control experiments. This simple and robust methodology provides a powerful tool to prepare 11C-labelled ureas previously inaccessible by existing methods and enable their utilisation for in vivo molecular imaging applications.

Supporting Information

 
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