7
036
I. Nouira et al. / Tetrahedron Letters 49 (2008) 7033–7036
certain amount of formamide may decompose under the used
experimental conditions and react with the formed benzoxazin-
Besson, T. J. Enz. Inhib. Med. Chem. 2007, 22, 577–583; (d) Logé, C.; Testard, A.;
Thiéry, V.; Lozach, O.; Blairvacq, M.; Robert, J.-M.; Meijer, L.; Besson, T. Eur. J.
Med. Chem. 2008, 43, 1469–1477.
4
-one.
In conclusion, we have demonstrated here that microwave-as-
6
.
Besson, T.; Chosson, E. Comb. Chem. High Troughp. Screening 2007, 10, 903–917.
7. Kostakis, I. K.; Elomri, H.; Seguin, E.; Iannelli, M.; Besson, T. Tetrahedron Lett.
007, 48, 6609–6613.
2
sisted rapid decomposition of formamide can be favourably used
as an inexpensive and easy to handle ammonia source for the syn-
thesis of nitrogen-containing heterocyclic rings. Our results can
also be considered as examples of the real specific effect of micro-
waves consisting in the capacity to specifically interact with
molecules according to their dielectric properties. Microwave
technology offers to chemists the possibility of a full control of
all reaction parameters with operational, economical and environ-
mental benefits over conventional methods.
8.
(a) Back, R. A.; Boden, J. C. Trans. Faraday Soc. 1971, 67, 88–96; (b) Kametani, T.;
Loc, C. V.; Higa, T.; Koizumi, M.; Ihara, M.; Fukumoto, K. J. Am. Chem. Soc. 1977,
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9.
Wan, Y.; Alterman, M.; Larhed, M.; Halberg, A. J. Comb. Chem. 2003, 5, 82–84.
Ò
10. The ‘hybrid’ microwave platform MultiSYNTH (Milestone S.r.l.), is a novel
dedicated microwave system for synthetic applications. It allows fast
a
reaction optimization providing high energy density in a single-mode like
configuration and an efficient scale-up (maximum working volume 300 ml)
through parallel synthesis in a multi-mode configuration. The instrument
features a special shaking system that ensures high homogeneity of the
reaction mixtures. It is equipped with an indirect pressure-control through
pre-calibrated springs at the bottom of the vessels shields and with both,
contact-less infrared pyrometer (IRT) and fibre-optic contact thermometer (FO)
for accurate temperature measurement. It is noteworthy that the IRT can be
calibrated directly on the temperature read by the FO to ensure the highest
Acknowledgements
TB thanks Milestone S.r.l. and the ‘Comité 76 de la Ligue Natio-
nale contre le cancer’ for financial support.
References and notes
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1
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1