S. A. Stone-Elander et al.
FULL PAPER
Chromatographic analyses were carried out on a Shimadzu GC14A(flame
ionization detector) coupled to a C-R5Aintegrator. All GC analyses were
run on a SGE BP1 dimethyl polysiloxane capillary column with injector
and detector at 2508C and helium as the carrier gas (flow 9 mLminÀ1). The
temperature program was as follows: isocratic at 608C for 4 min, increase
208CminÀ1 to 2408C, isocratic for 5 min followed by cooling for 7 min to
608C. The retention times were 4.2 and 7.1 min for 1 and 3, respectively. For
the microwave treatment, a monomodal cavity, Microwell 10 (Personal
Chemistry AB, Uppsala, Sweden) was used. The reaction vessels, described
previously in reference [14] were Pyrex tubes (11 mL) fitted with a screw
cap and a silicone/teflon septum. Temperature measurements were made
with a Nortech NoEMI TS-Series fibreoptic thermometer with a TP-21
probe.
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Synthesis of 3 (Table 1): Initial experiments (A) were performed by using 1
(300 mg) in 2 (4 mL). In the second group of experiments (B) 1 (4.4
4.6 mg) was dissolved in water (4 mL). To this solution 2 (30 mL) was added.
For the final group of experiments (C) 1 (0.96 mg) was dissolved in water
(100 mL). To
a 4 mL sample of this solution 2 (3 mL) was added.
Conventional experiments were performed in a magnetically stirred oil
bath. Microwave experiments were run at 150 W for 1 min. Between each
period of heating the vessel was allowed to cool to room temperature.
Analyses of reaction mixtures: For all UV analyses 3 mL samples were
analyzed against water references. For analysis of experiments from A, a
sample from the reaction mixture (1.5 mL) was dissolved in water (100 mL).
For experiments from section B, a reaction sample (20 mL) was taken and
diluted in water (3 mL). For section C a sample of the reaction mixture
(3 mL) was analyzed without dilution. This sample was recombined with
the rest of the reaction mixture before heating was resumed. For GC
analysis (section B) a 5 mL sample was taken directly from the reaction
mixture for injection.
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Acknowledgement
Support from the Swedish National Board for Technical Research (210
1997 494) and Personal Chemistry AB are gratefully acknowledged. This
project was, in part, initiated through the EU sponsored D10 COST
program (Innovative Methods and Techniques for Chemical Transforma-
tions).
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Received: November 22, 2001 [F3700]
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