Reaktion #347917

Reaktionsgleichung

2-n-butyl-1-(2-chlorophenyl)methyl-1H-imidazole

formaldehyde

sodium acetate

→

2-n-butyl-1-(2-chlorophenyl)methyl-5-hydroxymethyl-1H-imidazole

Ausbeute 41.1%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturto reflux for 40 hours under argon
3. 3
   EinengenThe reaction was concentrated in vacuo
4. 4
   workup.ADDITIONdiluted with water
5. 5
   Extraktionextracted with methylene chloride
6. 6
   WaschenThe extract was washed
7. 7
   Sonstigedried
8. 8
   Einengenconcentrated
9. 9
   Sonstigechromatographed over 600 g of silica gel with a gradient of ethyl acetate to 10% of methanol in ethyl acetate

Vorschrift

A mixture of 2-n-butyl-1-(2-chlorophenyl)methyl-1H-imidazole (95.5 g, 0.384 mol), 37% formaldehyde (500 mL), sodium acetate (80 g) and acetic acid (60 mL) was heated to reflux for 40 hours under argon. The reaction was concentrated in vacuo, and the residue was stirred with 500 mL of 20% sodium hydroxide solution for 4 hours, diluted with water and extracted with methylene chloride. The extract was washed, dried, and concentrated. The crude product (117 g) was flash chromatographed over 600 g of silica gel with a gradient of ethyl acetate to 10% of methanol in ethyl acetate to give 8.3 g of starting material, 24.5 g of a mixture of starting material and product, and 44 g (41%) of 2-n-butyl-1-(2-chlorophenyl)methyl-5-hydroxymethyl-1H-imidazole; mp 86°-88° C. (from ethyl acetate). Further elution provided the bis (4,5-hydroxymethyl) derivative; mp 138°-140° C. (from ethyl acetate).

Quelle