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References and notes
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9. Microwave reactions were conducted using a CEM
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The machine consists of a continuous focused microwave
power delivery system with operator-selectable power
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monitored using a calibrated infrared temperature control
mounted under the reaction vessel. All experiments were
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the vessel are stirred by means of a rotating magnetic plate
located below the floor of the microwave cavity and a
Teflon-coated magnetic stir bar in the vessel. General
procedure for the synthesis of cinnamaldehydes (1a–i): To a
stirred solution of p-substituted iodo/bromobenzene
2
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1
4
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0.100 g) in dry DMF (2 mL) in a sealed vessel was added
acrolein diethyl acetal (3 equiv), K CO (1.5 equiv) and
Pd(OAc) (3 mol %) under Argon atmosphere at room
temperature. The reaction mixture was then irradiated at
0 °C for 10 min (in some cases 2 cycles are required, see
8
2
3
2
2
9
6
Table 1). After cooling the reaction mixture was cautiously
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trimethyloxy silane (3 equiv), K
Pd(OAc) (3 mol %) under Argon atmosphere at room
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2 3
CO (1.5 equiv) and
1
1
1
1
2
9
0 °C for 10 min. After cooling, distilled out of DMF at
7
5
0–55 °C under vacuum. Water was added and the
reaction mixture was extracted twice with ethyl acetate,
then the organic layer was dried with sodium sulphate and
evaporated to dryness under reduced pressure. To the
residual mass diethyl ether was added and stirred at room
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1
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