[asa029]

Hello everyone! I have a tricky separation problem. I am preparing a series of 4,5-bis-substituted-1h-imidazoles using, among other things, TBAB as a PTC. During the workup, I have serious problems removing the TBAB from the product. I precipitate the imidazole using ammonia (also leading to the PTC precipitating). anyone have any tips or experience? Column (silica and various eluents) makes the product MORE impure, for some unknown reason

[Dan]

I've heard of washing out TBAF with dilute sodium citrate, but never got round to trying it myself. I guess it should work for TBAB too - I think the idea is that you form (TBA)₃(citrate), which is not very soluble in organics with respect to aqueous.