flash chromatography of amines- sighhh

[amy.j]

Hello all,

I'm trying to purify my crude reaction product and it is very polar (I've already got it stuck on a column). I found a paper that used a 50mm x 45cm flash chromatorgraphy column packed with 100 g of 'Lichroprep C18' from Merck and water:methanol (90:10) mobile phase.In the lit. it took 4 passes through a column to purify! Out of the 40 g of crude I'm expecting 1g of my target compound. Having only used standard silica gel in the past I couldn't believe the price of the stuff.

Does anyone know of any suppliers that are cheaper than Merck of C18 packing material (25-40 mesh)? Or if I can make my own from normal phase silica?

Any advice on columning amines is greatly appreciated!

Amy

[Gerhard Kratz]

You already found one of the cheapest products on the market.

Please ask for SPE cardridges from different sources to check which packing material will do the job, before handling large quantities. Some manufacturers might give you free test samples of their SPE products.