Sodium Hydroxide → (E)-4-methyl-2-styryl-1H-benzimidazole

A mixture of 2,3-diaminotoluene (2.44 g, 20 mmol), (E)-cinnamic acid (2.96 g, 20 mmol) and polyphosphoric acid (10 g) was heated to 180° C. for 90 min. The hot mixture was poured into water (100 ml), basified with 50% aqueous solution of sodium hydroxide and extracted with dichloromethane (3×100 ml). The combined extracts were washed with water (100 ml) and brine (100 ml), dried (magnesium sulfate) and concentrated to dryness. Purification by column chromatography (silica gel, 300 g; n-hexane/ethyl acetate (7/3)) yielded 0.61 g (13%) of the titled compound as red solids.

1. extractionextracted with dichloromethane (3×100 ml)
2. washThe combined extracts were washed with water (100 ml) and brine (100 ml)
3. dry with materialdried (magnesium sulfate)
4. concentrationconcentrated to dryness
5. customPurification by column chromatography (silica gel, 300 g; n-hexane/ethyl acetate (7/3))

ORD-Eintrag

ord-c5fd9300e7a34cb499021e518bfba359

Quelldatensatz

uspto-grants-2001_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06310079B1