07-10-04 09:11
No 518510
Having succeeded in producing methyl iodide a few months ago from iodine crystals, SWIM decided to try with iodine tincture directly. Unfortunately, he didn't take careful notes since he was skeptical that it would work.
Experimental: 385 ml 5% tincture is added to a 1L flask, and ~5g aluminum foil is added in small strips. The flask is then heated until the reaction begins and the fluid begins to boil. Once the fluid appears clear, the excess aluminum foil is filtered out, and the flask rigged for distillation. The isopropanol/water is distilled until about 25ml fluid remains. The distillate is a urine yellow color and smells slightly of iodine. Then 20ml MeOH is added, and the flask placed into the refrigerator. Over the next hour, 20ml freezer-chilled concentrated sulphuric acid is added in small portions with magnetic stirring. The contents of the flask became thick and creamy, and MeOH was added as necessary to maintain a stirrable consistency. The contents of the flask were transferred to a 250ml round bottom 14/20 flask which is then rigged for distillation and placed in a water bath. When heat is applied, the solution becomes somewhat brownish-red. The distillation is continued for some time, and after about 25ml of the 65C methanol fraction has come over, the distillation is ceased, and the contents of the receiving flask are chilled in the fridge for 30min. Then a saturated aqueous sodium chloride solution is added, and the bottom layer is collected with a syringe. Final yield: ~10ml MeI.
SWIM intends to do this again, and attempt to recover the iodine wasted in this experiment.
This is in no way an endorsement of Birch reduction.
