90
Hajipour, Mostafavi, and Ruoho
may be prepared according to the literature procedure 19 and is also commercially available
from Aldrich.
Iodination of Alcohol. General Procedure
In a mortar, a mixture of the alcohol (10 mmol), I2 (10 mmol, 2.5 g), triphenylphosphine
(10 mmol, 2.6 g), and 1-butyl-3-methylimidazolium bromide (0.2 g, 1 mmol, 10 mol%)
was ground with a pestle for the time specified in Table 1. The progress of the reaction
was monitored by TLC (n-hexane:EtOAc, 3:1) or GC. After disappearance of the alcohol
(
TLC), the reaction mixture was diluted with ether (25 ml) and filtered to remove solids. The
organic layer was washed with an aqueous solution of Na2S2O3 (10%, 10 ml), then H2O (2
10 ml). The organic layer was dried over anhydrous Na2SO4. The solvent was evaporated
×
under reduced pressure and the residue was purified by short column chromatography (n-
hexane:EtOAc, 3:1). This procedure was scaled up to 100 mmol of benzyl alcohol (10.8 g)
to give benzyl iodide in 80% yield in 5 min. The ionic liquid was not recoverable in this
procedure.
Acknowledgments
We gratefully acknowledge support received for this project from the Isfahan University
of Technology (IUT), IR Iran (A.R.H.) and Grants GM 033138, MH 065503, NS 033650
(A.E.R.) from the National Institutes of Health, USA. Further financial support from the
Center of Excellence in Sensor and Green Chemistry Research (IUT) is gratefully acknowl-
edged.
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