A method for preparing 1-(4-methanesulfonamidophenoxy)-2-[N-(4-methanesulfonamidophenethyl)-N-methylamino]ethane (Dofetilide) of formula I by sulfonylation of 1-(4-aminophenoxy)-2-[N-(4-aminophenethyl)-N-methylamino]ethane of formula II with N-methylsulfonyl-N-methylimidazolium chloride of formula III. ##STR00001##

A method for preparing 1-(4-methanesulfonamidophenoxy)-2-[N-(4-methanesulfonamidophenethyl)-N-methylamino]ethane (Dofetilide) of formula I by sulfonylation of 1-(4-aminophenoxy)-2-[N-(4-aminophenethyl)-N-methylamino]ethane of formula II with N-methylsulfonyl-N-methylimidazolium chloride of formula III. ##STR00001##

Process for preparing compound of formula (Ia) ##STR00001##

Process for preparing compound of formula (Ia) ##STR00001##

A compound represented by formula (I) or a salt thereof.

##STR00001##

In formula (I), R.sup.1 and R.sup.4 each independently represent a hydrogen atom, or an unsubstituted or substituted C1 to C6 alkyl group or the like. R.sup.2 represents a hydrogen atom, or an unsubstituted or substituted C1 to C6 alkyl group or the like. R.sup.3 represents an unsubstituted or substituted C1 to C6 alkyl group or the like. R.sup.5 represents a C1 to C6 haloalkyl group or the like. G represents an oxygen atom or a sulfur atom. R.sup.6 and R.sup.7 each independently represent a hydrogen atom, or an unsubstituted or substituted C1 to C6 alkyl group or the like. n represents 0 or 1. R.sup.8 and R.sup.9 each independently represent a hydrogen atom, or an unsubstituted or substituted C1 to C6 alkyl group. Ar represents an unsubstituted or substituted C6 to C10 aryl group or the like.

A method for preparing 1-(4-methanesulfonamidophenoxy)-2-[N-(4-methanesulfonamidophenethyl)-N-methylamino]ethane (Dofetilide) of formula I by sulfonylation of 1-(4-aminophenoxy)-2-[N-(4-aminophenethyl)-N-methylamino]ethane of formula II with N-methylsulfonyl-N-methylimidazolium chloride of formula III.

##STR00001##

A method for preparing 1-(4-methanesulfonamidophenoxy)-2-[N-(4-methanesulfonamidophenethyl)-N-methylamino]ethane (Dofetilide) of formula I by sulfonylation of 1-(4-aminophenoxy)-2-[N-(4-aminophenethyl)-N-methylamino]ethane of formula II with N-methylsulfonyl-N-methylimidazolium chloride of formula III.

##STR00001##

A method for preparing 1-(4-methanesulfonamidophenoxy)-2-[N-(4-methanesulfonamidophenethyl)-N-methylamino]ethane (Dofetilide) of formula I by sulfonylation of 1-(4-aminophenoxy)-2-[N-(4-aminophenethyl)-N-methylamino]ethane of formula II with N-methylsulfonyl-N-methylimidazolium chloride of formula III.

##STR00001##

The invention relates to a method for the preparation of bis(fluorosulfonyl)-imide and its derivatives at elevated temperature.

The invention relates to a method for the preparation of bis(fluorosulfonyl)-imide and its derivatives at elevated temperature.