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This fle is a part o the Rhodium site archive. This Aug 2004 static snapshotis hosted by Erowid

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' www.rhodium.ws ( ) '*hemistry Archive(

+arge,-cale #romination o 2*,

by -alvinorium / Eurotopian

22!.0g ' .011!mol( 2 !,dimetho&yphenethylamine hydrochloride wasdissolved in 32!m+ d 2 and poured into a + separating unnel. A solutiono 4!g ' . 2!mol( 5a in 3!m+ d 2 was then added care ully causing thesolution to become instantly cloudy and producing no observable heat. A paleamber oil 6uic$ly ell to the bottom and a ter an hour the clear bottom layerwas run o7 into a + erlenmeyer 8as$. The a6ueous layer was e&tracted w92&!0m+ :* and the e&tracts combined with the oil in the 8as$. As much aspossible o the :* was then removed by atmospheric distillation in a waterbath under stirring leaving a clear amber oil ';ig.

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The oil was dissolved under stirring in 100m+ >AA and the 8as$ placed in anice, 2 bath. A solution o !1.1m+ ' ??.2g@ .04mol( #r2 in 100m+ >AA wasadded under stirring in one portion and a re8u& column was 6uic$lyattached. A ter min the 8as$ was removed rom the ice, 2 bath and the

r&n mi&ture le t to stir at room temp. The 8as$ became warm and a terappro&. ?min spontaneously crystallised to a pale yellow,orange unstirrablemass ';ig. 2

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A ter this had cooled to room temp the re8u& column was replaced with astopper and the ca$e bro$en up by 10min o vigorous sha$ing. This causedthe r&n mi&ture to warm up again slightly indicating that the r&n did not goto completion when the mass precipited. The 8as$ was le t to stand at !* or

4hrs then fltered. The residue was washed with 2!0m+ Et Ac then groundunder !00m+ resh Et Ac with which it was then stirred at the bp o theEt Ac or !min. A ter cooling to room temp. the slurry was fltered and theresidue stirred w9another !00m+ boiling Et Ac cooled and fltered. Theresidue was air,dried to give 24?. g '0.3 B4mol@ 30C( 2 !,dimetho&y,4,bromophenethylamine hydrobromide as an odourless white powder ';ig. 1

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2*, *l used was o BB.3C purity.

#romine used was pre,chilled in a reeFer then allowed to warm slightly tomp.

5o signifcant 6uantities o product could be recovered rom the r&nsolvent and Et Ac washings.

The Et Ac purifcation is probably not the best one to use... a bettermethod may bee washing the crude Ac ,wet 2*,# #r with Et2 air,drying then dissolution in a minimum 6uantity o anhydrous %GA andprecipitation with Et2 .

:istillation o the :* rom the 2*, reebase should o course bee doneunder vacuum i possible.