790
A. Fˆınaru et al. / Tetrahedron Letters 43 (2002) 787–790
Scheme 5.
Table 3. Microwave synthesis of 10
Ratio 9/NIS (equiv.)
Solvent
Reaction time (min)
Irradiation power (W)
Yield of 9 (%)
1/1
1/1.5
Dichloromethane
Dichloromethane
14
11
60
60
88
94
In conclusion, we performed an access to the indole
core of melatonin analogs via palladium-mediated het-
eroannulation of internal alkyne 8 with o-iodoaniline
derivative 2. This synthesis is a further example of the
utility of microwaves in organic chemistry, confirming
that conventional thermal procedures can be substi-
tuted by microwave irradiation. The experimental
microwave conditions described in this paper are now
well established and our goal is to combine solid phase
synthesis with microwave heating in order to speed up
drug discovery process and also to demonstrate the real
interest of a such association.
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Acknowledgements
One of the authors (A.F.) is thankful to the Conseil
Re´gional du Centre for its financial support.
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