SU681056A1 - N-substituted phenyl esters of 5-alkoxypicolinic and 6-alkoxynicotinic acid as liquid nematic crystals - Google Patents

Description

the hyiochlor-tara chloride overflow is distilled off in vacuo. To the residue are added 20 ml of absolute benzene, 0.02 mol triethylamine and boiled for 2 hours in a water bath. To this mixture, with stirring and cooling (0-5 ° C), a solution of 0.01 mol of o-hexyloxyphenol in 10 ml of absolute benzene is added and left for 1 day at room temperature. Poured into a 5% sodium bicarbonate solution. The benzene layer is separated and washed until neutral with water, dried over sodium sulfate, the solvent is distilled off in vacuo and the residue is recrystallized to a constant melting point from hexane. 4-Hexnloxyphenyl ef1f 5-ethyl picolic acid was isolated in 54% yield. Tn 57, Ti 33.6 ° C.

Found,%: C 73.16, 72.96; H 7.55, 7JO; N 4.20, 4.13.

QoHasNOs.

CalculatedD; C, 73.36; H 7.69; N 4.27.

Similarly, nonyqeiai compounds listed in Table. one.

Example 2. p-Hexyloxyphenol ester of 6-butoxynicotinic acid. A mixture of 0.01 mol of 6-butoxynicotinic acid and 0.05 mol of thionyl chloride is boiled in a wax bath for 2 hours. An excess of thionyl chloride is removed in a vacuum, 20 ml of benzene absolute and 0.02 mol of triethylamine and boil are added to the residue. t 2 h in a water bath. To this mixture, while stirring and cooling (5C), a solution of 0.01 mol of p-hexnloxyphenol in 10 ml of absolute benzene is added and left for 1 day at room temperature. Poured into a 5% aqueous solution of sodium bicarbonate. The benzene layer is separated and washed until neutral.

reactions with water, dried over sodium sulfate and passed through a column (6 cm long) of alumina (1st degree of activity. The eluent is benzene. The solvent is distilled off in vacuum. The residue is recrystallized from hexa. Isolated with 45% yield of 4-hexyloxyphenyl Fir of 6-butoxynicotinic acid. Tn 45.8C; Ti 47.8C.

Found,%: C 70.90, 70.99; And 7.64, 7.56; N 3.80, 3.96.

CjjH29N04.

Claims (2)

Calculated,%: C 71.13; H 7.86; N 3.77. The compounds obtained in the same way are obtained in Table. 2. Below are the dielectric anisotropy of some compounds of the formula I% o C 00 v °° EsH "0 COQ CH" CH-CN coo temperature The compounds of general formula I are colorless crystalline substances, and in a liquid crystalline state, turbid liquids. They are stable during storage and operation in electro-optical cells. For example, when stored for 1 year at room temperature, the color and temperature of the phase transitions of the esters do not change, while the known pyridine derivatives age under similar conditions. The compounds of general formula I have also a lower 1: 2 comparison with the known phase transition temperatures. For example, p-hexyloxyphenyl ester of p-hexyloxybenzoic acid has so pl. 64.5 (8), and the corresponding 6-hexyloxynicotinic acid zirr melts at 42.3 ° C, and 5-hexyloxypicolinic acid at 54.7 ° C; p-hexyl oxyphenyl zfir p-amyloxybenzoic acid has so pl. 56.5 ° C (8), and the corresponding 6-amyloxynicotinic acid ester - (tp. 46, 5-amyloxypicolin 567 ° C. Thus, the compounds of general formula 1 are free of non-residues inherent in the well-known pyridine and alcoxane esters acids, they simultaneously have two advantages - lower melting points and chemical stability, which is important from the point of view of practical use of compounds of formula 1 in electro-optical devices. Formula of the invention p-Substituted phenyl esters of 5-alkoxy-picolinic and 6-alkoxy nicotinic acids of general formula (0) -1, x-wo V (D) «VtO) R2 SpNzp when n 2-7, RI CnHjrtrt R -CH CH-CN-rpynna; 1 0.1 as nematic liquid crystals. Sources of information taken into account during the examination 1.J. A. Nash, G. W. Gray, Mol. Cryst. Lig gryst. 25, 299 (1974). 2.D. Demus, H. Oemus, H. Zaschke Ftussige Kzistalle in Tabellen Leiprtg, 1974.