Found it on some kind of forum, and edited it a bit (regarding the labware I have on hand and added questions of interest to me, as well as some notes for clarity of understanding), what do you think?
In a 20-liter flask, 5 l of dry DCM, 9 g of lump aluminum (0.333 mol) and about a quarter of 80 g (0.5 mol) of bromine in a dropping funnel are added. After the beginning of the reaction the rest of the bromine is poured in and the flask is cooled in an ice bath. In the flask, 1480 g of 4-MPF and 5 L of DCM are added, after which approximately 80 g of bromine from a total of 1600 g is added. After discoloration of the reaction mixture the remaining bromine is added, keeping the internal temperature below 5°C. After the reaction is finished, 5 l of water is poured into the mixture, neutralized with baking soda and the organic layer is separated. The DCM is distilled off with a dephlegmator in a water bath at 60°C, after which the residue is dried. 60°C, after which the residue is dried under vacuum of a waterjet pump for half an hour. The mass from the flask is used in the next step without purification (yield expected about quantitative).
Questions:
1) Will the reaction of aluminum with bromine in dry DCM start
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The flask with the obtained BK-4 is provided with a reflux condenser, a magnetic stirrer and placed on an ice bath. Ten liters of dry diethyl ether are poured into the flask and BK-4 is dissolved.
An empty flask equipped with a small reflux condenser, a 2 L dropping funnel with pressure compensator and stove is filled with 200 ml of a 38% aqueous solution of methylamine. An 1800 mL of the same solution is poured into the funnel (Note 1). The end of the reflux condenser through a Drexel flask half filled with caustic caustic soda is connected to a glass tube leading up to the ether layer in the main flask.
After cooling the contents of the main flask to 5°C the contents of the generator flask are brought to a slight boil and the methylamine solution is gradually added, keeping the temperature in the main flask no higher than 15°C. After adding all the methylamine, lift the glass tube over the surface of the solution (note 2), remove the ice bath and leave to stand for 2-6 h. Ten liters of water is poured into the flask, stirred and the ether layer is poured off. The aqueous layer is washed 4 times with 2 L of ether (Note 3). The combined ether extracts are washed 2 times with 10 L of 1750 ml of diluted hydrochloric acid (Note 4). A 20% solution of sodium carbonate is added to this layer to pH = 8-9 (about 5 l). The aqueous layer is washed 5 times with 4 L of ether (note 5). The combined ether extracts are dried with calcined magnesium sulfate (Note 6), after which ~1 M hydrogen chloride ether solution (Note 7) is added until no more crystals precipitate. The ether solution is drained from the crystals, the latter are filtered on a Schott funnel and dried on the same funnel for 10 minutes.
Note 1: The total volume should be 2000 mL, the exact amount in the flask is not important.
Note 2. At the end of the methylamine current, the reaction mass can be sucked into a generator.
Note 3. In the original 2 times 5 L of ether each.
Note 4. 2.8 L of 6 M hydrochloric acid from note 7 and 320 ml of 36% hydrochloric acid diluted with water to 20 L.
Note 5. In the original 3 times 10 L of ether.
Note 6. Magnesium sulfate is added in portions of 50 g after 15 minutes until it stops clumping. About 270 g of magnesium sulfate is expected.
Note 7: In the same generator as for methylamine, 3200 mL of 36% hydrochloric acid is added and brought to a boil. The resulting hydrogen chloride is dried in a Drexel flask with 100 mL of concentrated sulfuric acid and saturated with 9 L of ether in a flask on an ice bath. The temperature should not be higher than 10°C. The obtained ether solution is stored in the refrigerator. In the flask remains 6 M hydrochloric acid with a volume of about 2.8 L.
Questions: How adequate is the slow addition of methylamine to BK-4?
In a 20-liter flask, 5 l of dry DCM, 9 g of lump aluminum (0.333 mol) and about a quarter of 80 g (0.5 mol) of bromine in a dropping funnel are added. After the beginning of the reaction the rest of the bromine is poured in and the flask is cooled in an ice bath. In the flask, 1480 g of 4-MPF and 5 L of DCM are added, after which approximately 80 g of bromine from a total of 1600 g is added. After discoloration of the reaction mixture the remaining bromine is added, keeping the internal temperature below 5°C. After the reaction is finished, 5 l of water is poured into the mixture, neutralized with baking soda and the organic layer is separated. The DCM is distilled off with a dephlegmator in a water bath at 60°C, after which the residue is dried. 60°C, after which the residue is dried under vacuum of a waterjet pump for half an hour. The mass from the flask is used in the next step without purification (yield expected about quantitative).
Questions:
1) Will the reaction of aluminum with bromine in dry DCM start
======
The flask with the obtained BK-4 is provided with a reflux condenser, a magnetic stirrer and placed on an ice bath. Ten liters of dry diethyl ether are poured into the flask and BK-4 is dissolved.
An empty flask equipped with a small reflux condenser, a 2 L dropping funnel with pressure compensator and stove is filled with 200 ml of a 38% aqueous solution of methylamine. An 1800 mL of the same solution is poured into the funnel (Note 1). The end of the reflux condenser through a Drexel flask half filled with caustic caustic soda is connected to a glass tube leading up to the ether layer in the main flask.
After cooling the contents of the main flask to 5°C the contents of the generator flask are brought to a slight boil and the methylamine solution is gradually added, keeping the temperature in the main flask no higher than 15°C. After adding all the methylamine, lift the glass tube over the surface of the solution (note 2), remove the ice bath and leave to stand for 2-6 h. Ten liters of water is poured into the flask, stirred and the ether layer is poured off. The aqueous layer is washed 4 times with 2 L of ether (Note 3). The combined ether extracts are washed 2 times with 10 L of 1750 ml of diluted hydrochloric acid (Note 4). A 20% solution of sodium carbonate is added to this layer to pH = 8-9 (about 5 l). The aqueous layer is washed 5 times with 4 L of ether (note 5). The combined ether extracts are dried with calcined magnesium sulfate (Note 6), after which ~1 M hydrogen chloride ether solution (Note 7) is added until no more crystals precipitate. The ether solution is drained from the crystals, the latter are filtered on a Schott funnel and dried on the same funnel for 10 minutes.
Note 1: The total volume should be 2000 mL, the exact amount in the flask is not important.
Note 2. At the end of the methylamine current, the reaction mass can be sucked into a generator.
Note 3. In the original 2 times 5 L of ether each.
Note 4. 2.8 L of 6 M hydrochloric acid from note 7 and 320 ml of 36% hydrochloric acid diluted with water to 20 L.
Note 5. In the original 3 times 10 L of ether.
Note 6. Magnesium sulfate is added in portions of 50 g after 15 minutes until it stops clumping. About 270 g of magnesium sulfate is expected.
Note 7: In the same generator as for methylamine, 3200 mL of 36% hydrochloric acid is added and brought to a boil. The resulting hydrogen chloride is dried in a Drexel flask with 100 mL of concentrated sulfuric acid and saturated with 9 L of ether in a flask on an ice bath. The temperature should not be higher than 10°C. The obtained ether solution is stored in the refrigerator. In the flask remains 6 M hydrochloric acid with a volume of about 2.8 L.
Questions: How adequate is the slow addition of methylamine to BK-4?