The Vespiary

The Hive => Serious Chemistry => Topic started by: sTAMPy on May 11, 2000, 08:39:00 PM

Title: Grignard
Post by: sTAMPy on May 11, 2000, 08:39:00 PM
Hello, new to THE HIVE. One question if I may, where can I find the steps tp preparing the Grignard reagent using, specifically, cyclopentyl bromide and magnesium. I have searched for days in Vogels, but I have not been able to find this particular preparation in enough detail, inc. glass and chem req'd. Thank you for your help.

Title: Re: Grignard
Post by: Rhodium on May 12, 2000, 10:42:00 AM
All grignard reagents are made in the same fashion, just substitute cyclopentyl bromide with the alkyl halide used in any prep in Vogel's. 

http://rhodium.lycaeum.org (http://rhodium.lycaeum.org)

Title: Re: Grignard
Post by: zephler on May 12, 2000, 06:28:00 PM
Yup, just add yer alkyl halide to some ether, then add Mg metal in excess (slowly, exothermic), and voila!

Title: Re: Grignard
Post by: sTAMPy on May 14, 2000, 05:04:00 PM
Thankyou Rhodium and zephler. It's funny, after posting my request, I looked at the whole Grignard thing again (in Vogel's), and it clicked, some of these things (organic chemistry) only LOOK difficult due to the chemical names and  procedures. As a Chef [food] I should have known. Thankyou for your help and prompt replies.

Title: Re: Grignard
Post by: zephler on May 14, 2000, 10:35:00 PM
Chemists hide behind big words and phrases so that they sound intelligent, when really its just basic stuff we talk about

Title: Re: Grignard
Post by: Methoxy on May 17, 2000, 10:01:00 AM
Have anyone ever tryed makeing ephedrine from the grignard reagent phenylmagnesiumbromide and N,N-dimethyl-2-aminoethanal, or isn't the procedure possible. Could you btw syntesise ephedrine in other ways?


Meth~o~xy
Title: Re: Grignard
Post by: Rhodium on May 17, 2000, 02:04:00 PM
That reaction would produce N-methyl-ephedrine, which would be reduced to N,N-dimethyl-amphetamine, which is not active.

http://rhodium.lycaeum.org (http://rhodium.lycaeum.org)