will this method work?
A solution of 3.00 grams (10 mmol) of codeine in 60 ml of dry dimethylformamide was degassed under nitrogen by repeatedly stirring under vacuum, followed by inletting nitrogen. Following the addition of 3.00 grams (26.7 mmol) of potassium tert-butoxide, the degassing process was repeated, and 3.0 ml (32.7 mmol) of n-propanethiol was injected by syringe. The mixture was stirred at 125°C under nitrogen for 45 min (similar results at 110°C for 3h), cooled, and quenched with 3.0 ml of acetic acid. The solvent was removed under high vacuum, and the residue dissolved in 30 ml of 1N hydrochloric acid. The acid solution was washed with several portions of ether, treated with 5ml of 20% sodium bisulfite, and alkalized to pH 9 with ammonium hydroxide. The precipitated solid was collected, washed with water, and dried in vacuo (100°C) to leave 2.30g (80%) of morphine as tan crystals.
how and why is the n-propanethiol injected by syringe?
