napoleon9 - 10-2-2011 at 14:03
My teacher advice me that i make dry hex-1-yne by CaH2, but My Lab haven't it now. Please give me some advice.
thanks
madscientist - 10-2-2011 at 14:19
I assume you meant CaC<sub>2</sub>. What are the other reagents and conditions?
napoleon9 - 10-2-2011 at 14:31
I'm sorry. I remember incorrect. Dry hex-1-yne by MS 4A. Please give me some advice.
thanks
Paddywhacker - 10-2-2011 at 18:34
mmmm.... MS 4A .... tricky.
MS 4A doesn't have any carbons in it, and dry hex-1-yne has at least six per molecule, so you are going to need something else..... most probably
something with carbons in it. Six carbons per molecule might be handy. Maybe glucose .... no ... too solid. I'm out of ideas.
madscientist - 10-2-2011 at 21:45
I think he means drying hex-1-yne with molecular sieves 4A.
nitric - 11-2-2011 at 11:40
Drying with CaCl2 and molecular sieves 4A should be dry enough for most reactions. If we had details of what you are going to do with the hex-1-yne,
we may be able to be a bit more detailed.
napoleon9 - 12-2-2011 at 09:03
some my friend advice me that hexyne are dry by CaO or MgSO4 ????
If my Lab haven't MS 4A. How do you do dry hexyne ? why ? explain ? 
Please give me some advice
Thanks
napoleon9 - 22-2-2011 at 21:52
hex-1-yne is Merck product, 98%. I don't find MS 4A in HO CHI MINH city, VIET NAM. how do you make drying hex-1-yne ? when you haven't MS 4A.
Please give me some advice .....
thank you 
nitric - 23-2-2011 at 07:40
You use other drying reagents, such as CaCl2, CO, Ca2C
peach - 23-2-2011 at 08:31
Drying agents
not_important - 23-2-2011 at 11:33
Note the using metal hydrides or reactive metals with 1-ynes may lead to replacement of the terminal hydrogen, forming H2(g). Strong bases can cause
isomerisation, especially if heated.
If the alkyne is really wet, perhaps start with Na2SO4, else go right to MgSO4. If there is likely to be alcohols in the product, use CaCl2 as the
preliminary drying agent. Follow by a polishing with CaSO4, low capacity thus the pretreatment with one of those other sulfates, but will make it
pretty dry. Although not quite as good as 3A or 4A sieves (it does better than silica gel), CaSO4 is cheap, easy to obtain, and easy to regenerate,
and is compatible with most organics (like Na2SO4 is as well).
napoleon9 - 3-3-2011 at 20:33
i read book purification of lab
"1-Hexyne [693-02-7] M 82.2, b 12.5o/75mm, 7 1o/760mm
Distil it from NaBH4 to remove peroxides. Stand over sodium for 24hours, then fractionally distil it under reduced
pressure"
i bought hexyne of Merck 98%. If external cooling is provided by ice dry, Na wire was fire over bottle hexyne. After 24h, solution in bottle has red
yellow. it was colourless solution when it was into filter paper.
"correct or incorrect ????? "
If i made drying hexyne by silica gel ???? correct or incorrect ?????
can you show me some example ????
thanks