Acetic Anhydride → HCID 13651195, compound

Participants

Reaction Steps

A mixed solution of 3-hydroxy-6-methylpyridine (3.3 g, 0.03 mol), 4-cyanobenzaldehyde (3.9 g, 0.03 mol) and acetic anhydride (6.1 g, 0.06 mol) was heated under reflux for 25 hours, followed by cooling the reaction mixture, thereafter adding toluene (30 cc), separating the resulting solids by filtration, washing the solids with toluene till the toluene filtrate became colorless, adding methanol (20 cc) and conc. hydrochloric acid (20 cc) to the solids, heating the mixture for 3 hours, cooling, neutralizing with aqueous ammonia, filtering, dissolving the resulting precipitate in ethanol (50 cc), adding Pd-C catalyst (0.3 g), and subjecting the mixture to catalytic reduction at room temperature and the atmospheric pressure. After completion of the reaction, the catalyst was filtered off, followed by distilling off the solvent under reduced pressure and recrystallizing the remaining solids from a mixed solvent of methanol/water (2:1) to obtain 3-hydroxy-6-[β-(4-cyanophenyl)ethyl]pyridine (1.4 g). To this compound were then added toluene (50 cc) and pyridine (3 cc), followed by adding 4-pentoxybenzoyl chloride (1.4 g) to the resulting solution, allowing the mixture to stand overnight, washing with water, then with 2N-hydrochloric acid, further with 2N-NaOH aqueous solution and finally with water till the washing water became neutral, distilling off toluene under reduced pressure and recrystallizing the remaining solids from ethanol to obtain the objective 6-[β-4-(cyanopheny)ethyl]-3-(4-pentyloxybenzoyl)pyridine (0.7 g) having as its phase transition points, a crystalline-nematic point (C-N point) of 107.8°-108.7° C. and a nematic-clearing point (N-I point) of 156.5°-156.8° C.

Provenance & Evidence