4588
Y. Ge, L. Hu / Tetrahedron Letters 48 (2007) 4585–4588
7. Imamura, S.; Kurasawa, O.; Nara, Y.; Ichikawa, T.;
Nishikawa, Y.; Iida, T.; Hashiguchi, S.; Kanzaki, N.;
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Koehler, K.; Grynfarb, M.; Goos-Nilsson, A.; Sandberg,
J.; Osterlund, M.; Barkhem, T.; Hoglund, M.; Wang, J.;
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that simple esters are more readily hydrolyzed than the
formamide group under these conditions. We also
selected two carbamates (12a–b) to test the compatibility
of these conditions with carbamates. Microwave heating
of compounds 12a and 12b for 8 and 12 min exclusively
gave the desired deformylated product 13a and 13b in a
conversion yield of 97% and 92%, respectively (Table 2,
entries 7 and 8). No hydrolysis of the carbamates was
observed.
9. Matulenko, M. A.; Lee, C. H.; Jiang, M. Q.; Frey, R. R.;
Cowart, M. D.; Bayburt, E. K.; DiDomenico, S.; Gfesser,
G. A.; Gomtsyan, A.; Zheng, G. Z.; McKie, J. A.;
Stewart, A. O.; Yu, H. X.; Kohlhaas, K. L.; Alexander, K.
M.; McGaraughty, S.; Wismer, C. T.; Mikusa, J.; Marsh,
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K.; Nishida, K.; Shimbo, Y.; Takanishi, Y.; Watanabe, J.;
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In conclusion, a set of microwave-assisted deformyl-
ation conditions were developed to efficiently remove
the formyl group from N-aryl formamides using basic
Al2O3 as the solid support and KF as the catalyst. Car-
bamates and bulky t-butyl esters were not affected while
simple esters were hydrolyzed under these conditions.
This method should be useful in organic synthesis, espe-
cially for the synthesis of electron-deficient secondary
aromatic amines.
Acknowledgments
We gratefully acknowledge the financial support of a
research grant from the State of New Jersey Commis-
sion on Cancer Research and a research scholar grant
from the American Cancer Society.
13. Gedye, R.; Smith, F.; Westaway, K.; Ali, H.; Baldisera, L.;
Laberge, L.; Rousell, J. Tetrahedron Lett. 1986, 27, 279–
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19. The commercially available 40% KF/Al2O3 can also be
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20. Although the deformylation reactions on a solid support
were performed safely with a domestic microwave in
loosely-capped vials under atmospheric pressure, we
found, in a comparison study, that the same reaction
using compound 6 (Table 1, entry 11) was more efficiently
done (<5 min) with a commercial microwave synthesizer
(CEM Discoverꢁ with ChemDrive 3.6.0 software) in a
sealed tube under pressure at 100 ꢂC.