Synthesis of symmetrical and unsymmetrical ureas using unsymmetrical diaryl carbonates

Article abstract of DOI:10.1080/00397919608003622

Appropriately substituted unsymmetrical diaryl carbonates react smoothly with primary amines to give the carbamates derived by nucleophilic displacement of the less electron rich aromatic substituent. Subsequent treatment of the carbamates with primary and secondary amines gives either symmetrical or unsymmetrical ureas in excellent yield and the overall process can be carried out as a 'one pot' operation. Acetonitrile is the preferred solvent and addition of DBU facilitates the carbamate → urea transformation.

Full text of DOI:10.1080/00397919608003622

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Synthetic Communications:
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Synthetic Organic Chemistry
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Synthesis of Symmetrical
and Unsymmetrical Ureas
Using Unsymmetrical Diaryl
Carbonates
Richard Freer a & Alexander McKillop b
a Synthetic Chemistry Department , SmithKline
Beecham Pharmaceuticals , New Frontiers
Science Park, Third Avenue, Harlow, Essex, CM19
5AW, UK
b School of Chemical Sciences, University of East
Anglia , Norwich, NR4 7TJ, UK
Published online: 21 Aug 2006.
To cite this article: Richard Freer & Alexander McKillop (1996) Synthesis of
Symmetrical and Unsymmetrical Ureas Using Unsymmetrical Diaryl Carbonates,
Synthetic Communications: An International Journal for Rapid Communication of
Synthetic Organic Chemistry, 26:2, 331-349, DOI: 10.1080/00397919608003622
To link to this article: http://dx.doi.org/10.1080/00397919608003622
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