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43
iodinative decomposition or,
thermolysis reactions,
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under mild conditions, by enzyme reactions.
method, the decarboxylation takes place in a paste chemi-
cal medium during the microwave irradiation.
Initially, pyruvic acid, phenylhydrazine derivative, and
zinc chloride were mixed thoroughly. Next, phosphorus
pentachloride was added and the mixture stirred further.
A paste like material resulted which was irradiated with
In our
1
1
1. Tietze, L. F.; Major, F. Eur. J. Org. Chem. 2006, 10, 2314–2321.
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4
6
microwaves. The hot spots created in a paste during the
microwave irradiation act like catalytic centers
3
3,47
result-
ing in the formation of the corresponding indoles in high
yields.
The combination of simple experimental, easy separa-
tion of the indoles, high product purity, short reaction
time, and high yields are advantages of this method. The
synthesized products are shown in Table 1.
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6. Fischer, E.; Hess, O. Ber. 1884, 17, 559.
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(
0.6 mmol) were thoroughly mixed in a 25 ml Pyrex beaker.
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mixing was continued until a paste resulted. The paste
was irradiated in a microwave oven (k = 12.2 cm) for the
required time (see Table 1). Water (50 ml) was added and
the aqueous extracted with dichloromethane (50 ml ꢁ 2).
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the solvent evaporated. The residue was recrystallized from
ether to give the indole derivatives (Table 1).
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