Reaction #631646

Reaction equation

StepA

benzyl chloride

compound

8-hydroxy-2-methyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine hydrochloride

sodium hydride

→

title compound

8-benzyloxy-2-methyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine

Solvents

DMF

Conditions

Workup

1. 1
   Temperaturecooled
2. 2
   workup.STIRRINGThe resulting mixture is stirred 30 min. on an ice-water bath
3. 3
   OtherThe solvent was evaporated off at reduced pressure
4. 4
   workup.ADDITIONTo the residue there was added water
5. 5
   workup.ADDITIONwith a 1:1 mixture of methylenechloride and ether
6. 6
   WashThe combined extracts were washed with brine
7. 7
   Otherdried over Na2SO4and the solvent
8. 8
   Otherevaporated at reduced pressure
9. 9
   OtherThe oily residue was chromatographed on silica gel
10. 10
    workup.ADDITIONa 1:1 mixture of acetone and methylene chloride as eluant

Procedure

This reaction mixture (which contains the free base of the compound of StepA) was added stepwise to an ice cooled, stirred suspension of 1.02 g of 50%dispersion of sodium hydride. The resulting mixture is stirred 30 min. on an ice-water bath. To this cold suspension (which contains the alkoxide ofthe compound of Step A) there was added a solution of benzyl chloride (2.48g) in DMF. The resultant mixture was stirred in an ice bath for 5 min., at room temperature for 5 min., and then in a heating bath at 85°-90° C. for 1.5 hrs. The solvent was evaporated off at reduced pressure. To the residue there was added water and the mixture wasextracted three times with a 1:1 mixture of methylenechloride and ether. The combined extracts were washed with brine, dried over Na2SO4and the solvent evaporated at reduced pressure. The oily residue was chromatographed on silica gel, using a 1:1 mixture of acetone and methylene chloride as eluant. The title compound was obtained as a yellow oil with the following PMR spectrum (DMSO-d6): 2.08(3H,s); 1.7-2.2(4H,m); 3.65-4.1(2H,m); 4.42(IH, deformed triplet); 4.70(2H,s); 6.73(IH,s); 7.30(SH,s).

Source