Synfacts 2005(2): 0266-0266  
DOI: 10.1055/s-2005-916090
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

SPOS of Heterocycles via Wang Resin-Bound Diazocarbonyls

Contributor(s): Yasuhiro Uozumi, Masahiro Kimura
M. Yamashita, S.-H. Lee, G. Koch, J. Zimmermann, B. Clapham*, K. D. Janda*
The Scripps Research Institute, la jolla, USA, and Novartis Pharma AG, Switzerland
Further Information

Publication History

Publication Date:
25 October 2005 (online)

Significance

Oxazolones 2, oxazoles 3, and imidazolones 4 were synthesized by N-H insertion/cyclization/cleavage sequences using the Wang resin-bound α-diazo-β-ketoesters 1 as key building blocks in excellent purities and good yields (up to 99% purity). The diazocarbonyl intermediates 1 were prepared on the polymer support by trans­esterification of the Wang resin and tert-butyl-β-ketoesters followed by treatment with dodecylbenzenesulfonyl azide in the presence of Et3N.