Reaction #2486

Reaction equation

N,N'-bis-(imidazolin-2-yl)ethylenediamine hydrobromide

potassium hydroxide

→

N,N'-bis(imidazolin-2-yl)ethylenediamine

Solvents

methanol

Conditions

Workup

1. 1
   workup.ADDITIONwas then added
2. 2
   OtherAfter potassium bromide precipitated
3. 3
   Filtrationwas filtered out
4. 4
   Othermethanol was removed by distillation

Procedure

In 1,400 ml of methanol, 200 g of N,N'-bis-(imidazolin-2-yl)ethylenediamine hydrobromide was dissolved and to the solution, 63 g of 85% potassium hydroxide was then added and stirred for 1 hr at 25° C. After potassium bromide precipitated was filtered out, methanol was removed by distillation to obtain N,N'-bis(imidazolin-2-yl)ethylenediamine as a solid. In 680 ml of ethanol, 34 g (0.1 mol) of 4-(phenylsulfonyl)phenylsulfonylacetic acid was heated to dissolve. To the cooled solution was then added 9.8 g (0.05 mol) of N,N'-bis(imidazolin-2-yl)ethylenediamine in ethanol and the resulting mixture was cooled to 10° C. A crystal precipitated was filtered off, washed and air-dried to obtain 42 g of the intended Compound 3 as crystals. NMR (heavy methanol): δ8.2 (q, 8H), 8.0 (m, 4H), 7.6 (m, 6H), 3.7 (s, 8H), 3.4 (s, 4H).

Source