	US 7,501,522 B2
	Method for the production of purified 1,3-substituted imidazolium salts
Matthias Maase, Speyer (Germany); and Klemens Massonne, Bad Dürkheim (Germany)
Assigned to BASF Aktiengesellschaft, Ludwigshafen (Germany)
Appl. No. 10/564,871 PCT Filed Jun. 30, 2004, PCT No. PCT/EP2004/007076 § 371(c)(1), (2), (4) Date Feb. 06, 2006, PCT Pub. No. WO2005/019183, PCT Pub. Date Mar. 03, 2005.
Claims priority of application No. 103 33 239 (DE), filed on Jul. 21, 2003.
Prior Publication US 2006/0149074 A1, Jul. 06, 2006
Int. Cl. C07F 9/80 (2006.01); C07F 5/02 (2006.01)

U.S. Cl. 548—102 [548/107; 548/110]

14 Claims

1. A process for preparing purified 1,3-substituted imidazolium salts of the formula (I)

where

the radicals R¹, R², R³and R⁴are each, independently of one another, a carbon-comprising organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic radical which has from 1 to 30 carbon atoms and may comprise one or more heteroatoms and/or be substituted by one or more functional groups or halogens, where adjacent radicals R¹and R², R²and R³or R³and R⁴may also be joined to one another and the radicals R²and R³may each also be, independently of one another, hydrogen, halogen or a functional group;

and

A^a− is the partly or fully deprotonated anion of an inorganic or organic protic acid H_aA (III), where a is a positive integer and indicates the charge on the anion,

which comprises reacting a 1,3-substituted imidazolium salt of the formula (II),

where the radicals R¹, R², R³and R⁴are as defined above and

the anion Y^y− is the partly or fully deprotonated anion of an inorganic or organic protic acid

H_yY (IV),

where y is a positive integer and indicates the charge on the anion,

with a strong base at from 20 to 250° C. while distilling off the 1,3-substituted imidazol-2-ylidene formed, wherein the 1,3-substituted imidazol-2-ylidene which has been distilled off is brought into contact in the gaseous state with the protic acid

H_aA (III)

and/or the 1,3-substituted imidazol-2-ylidene which has been distilled off is passed in the gaseous or condensed state into a receiver comprising the protic acid H_aA (III).