10-15-03 04:19
No 464667
SWIM has read a dozen posts but none say anything concrete. Topic says it all...
Peace -
(Newbee)
10-15-03 06:07
No 464693
Swix has successfully scaled up and down al/hg aminations and alkylations, the key to his success being that he GRADUALLY scaled up and down, because there has come a point for him where he discovered that the ratio of reagents required for the highest yield change slightly once you signifigantly scale up or down. If you would describe your reaction, maybe more help could be provided.
SwiX is a guy who thinks MickyFinn is hella HAWT
(Hive Bee)
10-16-03 17:37
No 464988
The Al/Hg is not very easily scaled up...unless you have some HUGE glassware. The MM version is claimed to bee right on, but many bees here have suggested using a 3 litre flask instead of a 2 litre. Why? Beecause this reaction is VIOLENT, and you don't want it to run away from you. If you want to scale this monster up, you're going to need a huge flask and a loooong condenser. Trust me, this is not one you want to get away from you! good luck peace
PS- if you're going to run it with MM's ratios, I also suggest a 3 litre flask and at LEAST 400mm of condenser length.
D.A.R.E. = Drugs Are Really Exciting
(Hive Bee)
10-16-03 18:58
No 465003
They are both right NEO. Of course it can be done, and
yes, the glassware you would need might become an
issue. Although I am going to have to add that Nitro says
the reaction is "VIOLENT", no it is not that violent. IF you
do what you are NOT supposed to do then yes it MAY
get out of hand. Things that can cause this is adding too
much HgCL2 or too much Nitro. It is recommended that
using at least 2L reaction flask is the way to go, and a 3
is better. That is true, you can get away with a 2L but a
3L would give you more "headroom" for your reaction to
run. The reason you will need at least 400mm of conde-
nsor room is because the MeOH at the rate it is evaping
may cause a kind of "blockage" if not properly condensed
therefor giving a temporary "no relief of pressure" do to the
MeOH gas building up inside, too much pressure and it
will shoot drops of MeOH out of your setup thus defecting
your rxn. If this happens just add a little MeOH to your it.
But I hope this does not because that meant you didn't
follow the writeup very well. Depending on how much you
want to scale up there is a great writeup on rhodium's
page that shows how you can accomplish this using a 5
gallon bucket and overhead stirring, with I believe is 800mm
worth of condensors. It looks like a great setup for bulk
amination. A trip to the hardware store would be in order.
Well just becareful and this is a part where deviation from
the writeup won't payoff UNLESS you are a chemist and
knows exactley what you are doing.
(arrogant bee of the day)
10-18-03 11:54
No 465381
Al/Hg can be scaled up nicely, nitro no! Two different reactions, but the way you stated the question would mean classic Al/Hg not nitro.
More info would be nice, otherwise all these people replied to your thread for nothing.
I'm not fat, I'm just too short for my weight.
http://www.whatreallyhappened.com
(Hive Bee)
10-18-03 12:03
No 465383
Al/Hg with nitro can be scaled if you:
A. Have balls. Balls are a must.
B. Have the right equipment. Industrial magnetic stirrer, 45/50 joint glassware. A huge stirbar.
C. Fans!! It's all about the high powered fans!!! It's amazing what a few fans can do to keep the rxn vessel cool.
D. Carboys with spigots to use as a sep.
I wouldn't scale this rxn up any more than 6x MM's ratios, any more that... well, talk to Baal.
http://www.greenspun.com/bboard/q-and-a-