conducter
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phenethyl bromide from bromobenzene?
Is it possible to make phenethyl bromide (2-bromoethyl)benzene from Bromobenzene?
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not_important
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Yes :
make the Grignard reagent from bromobenzene, add it to a slight excess of BrCH2CH2I (1-bromo-2-iodo-ethane) with good stirring.
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chemrox
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I like it but wouldn't the dihalo alkane be harder to come by?
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Nicodem
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Not_important, I don't think that would work. Unless you had in mind a Kumada coupling with an organometalic catalyst like described in the paper I
recently uploaded: https://sciencemadness.org/talk/viewthread.php?tid=9310&...
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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chemrox
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Isn't that where he was going? We all just read that paper, thanks to you.
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Sergei_Eisenstein
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I would try the following:
1) organomagnesium of halobenzene + ethylene oxide -> 2-phenylethanol
2) 2-phenylethanol + (several possible reagents) -> (2-bromoethyl)benzene
damnant quod non intelligunt
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garage chemist
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2-phenylethyl bromide is industrially made by free-radical addition of HBr to styrene. Anhydrous gaseous HBr and less than 30% styrene in an aliphatic
hydrocarbon solvent (e.g. heptane) is used, at elevated temperature, and with a radical initiator (dibenzoyl peroxide, AIBN, etc...).
The product needs proper purification, although almost no 1-phenethyl bromide is formed in the reaction.
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Antwain
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I cant imagine that getting the anhydrous HBr is going to be especially easy if you can't buy it in a pressurised bottle
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chemrox
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I would follow Sergei's example if I hadn't been able to buy it. Acros, Spectrum, Alfa Aesar and etc. all have it. Not so dear as to make using a
gaseous epoxide worthwhile... you would need a hood with good evacuation and I suppose there's a place you could get a lecture bottle of it filled but
I've no idea where that would be. All my gasses come from a welding supplier.
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