JPH0791208B2 - Optically active alkoxy biphenyl ether compound - Google Patents

Description

The present invention relates to a specific optically active biphenyl ether compound, and more particularly to an alkoxy group-containing alkoxy biphenyl ether compound having an asymmetric carbon atom.

Alkoxybenzene derivatives having asymmetric carbon atoms have been attracting attention in recent years as intermediates for liquid crystal chemicals, and in particular, alkoxybiphenyl compounds, alkoxyphenylpyrimidine compounds, alkoxybenzoic acid derivatives, etc. are used as ferroelectric smectic liquid crystal chemicals. Are known.

The alkoxy group in these liquid crystal compounds is 6
-Methyloctoxy group, 2-methylbutoxy group and the like are known, but these compounds have a problem that the usable temperature range is appropriate, or the orientation stability is poor, and therefore they are practical. It wasn't.

For this reason, strong induction liquid crystal compounds, including the basic skeleton of the compound, are currently being investigated.

As a result of intensive studies on the alkoxybiphenyl compound having an asymmetric carbon atom, the present inventors have found that the compound represented by the following general formula (I) has excellent optical activity.

In the formula, R ₁ represents a linear alkyl group having 1 to 18 carbon atoms, R ₂ represents a hydrogen atom or an alkyl group having 1 to 11 carbon atoms, and * represents an asymmetric carbon atom. Hereinafter, the present invention having the above gist will be described in more detail.

The compound represented by the general formula (I) can be easily produced, for example, by reacting an optically active p-alkoxy-substituted biphenol with an alkyl halide or tosylate in the presence of an alkali compound.

Next, the present invention will be described with reference to examples.

Example 1 Synthesis of (R) -4- (6 ″ -chloro-4 ″ -methylhexyloxy) -4′-octyloxybiphenyl ([α] = + 3.75 ° (27 ° C., C = 1, chloroform solution ) (R) -4- (6 ″ -chloro-4 ″ -methylhexyloxy) -4′-hydroxybiphenyl 3.19 g, fine powder sodium hydroxide 0.42 g and methyl ethyl ketone 30 ml are charged and stirred under reflux for 1 hour. Here, n-
Octyl bromide (2.03 g) was added, and the mixture was stirred under reflux for 12 hours.

The reaction mixture was poured into a large amount of 5% hydrochloric acid aqueous solution, and the precipitated solid was filtered. After washing with water and drying, recrystallization from methanol / ethanol (1/1) gave a white powder having a melting point of 80.7 ° C.

As a result of infrared spectroscopic analysis, the obtained product had the following characteristic absorptions and was confirmed to be the target product.

^{3050cm -1 (vw), 2940cm -1} (s), 2860cm -1 (s), 1605cm -1 (s), 1565cm -1 (vw), 1500cm -1 (s), 1465cm -1 (s), 1390cm ^{-1 (m), 1325cm -1 (} vw), 1270cm -1 (s), 1240cm -1 (s), 1180cm -1 (m), 1135cm -1 (w), 1040cm -1 (m), 1000cm - ^{1 (vw), 965cm -1 (} w), 920cm -1 (vw), 820cm -1 (s), 725cm -1 (w), 655cm -1 (w), 600cm -1 (w), 515cm -1 (W) Moreover, the optical rotation of the obtained product is shown below.

[Α] _D = + 1.69 ° (25 ° C., C = 1, chloroform solution) In addition, 2.98 g of 4-octyloxy-4′-hydroxybiphenyl and [α] = − 1.76 ° (27 ° C., C = 2, (Chloroform solution), which was the same as that synthesized in the same manner from 3.20 g of (R) -6-chloro-4-methylhexanol p-toluenesulfonic acid ester.

Example 2 Synthesis of (R) -4- (6 ″ -chloro-4 ″ -methyloctyloxy) -4′-octyloxybiphenyl [α] _D = −1.00 ° (28 ° C., C = 1, chloroform solution) (R) -4- (6 ″ -chloro-4 ″ -methyloctyloxy) -4′-hydroxybiphenyl was used in the same manner as in Example 1 to obtain a white powder having a melting point of 75.6 ° C.

As a result of infrared spectroscopic analysis, the obtained product had the following characteristic absorption, and the desired (R) -4- (6 ″ -chloro-4 ″) was obtained.
-Methyloctyloxy) -4'-octyloxybiphenyl was confirmed.

^{3050cm -1 (vw), 2940cm -1} (s), 2860cm -1 (s), 1605cm -1 (s), 1565cm -1 (vw), 1500cm -1 (s), 1465cm -1 (s), 1385cm ^{-1 (m), 1320cm -1 (} vw), 1270cm -1 (s), 1245cm -1 (s), 1180cm -1 (m), 1130cm -1 (w), 1040cm -1 (m), 995cm - ¹ (vw), 960cm ^-1 (vw), 905cm ^-1 (vw), 825cm ^-1 (s), 720cm ^-1 (vw), 660cm ^-1 (vw), 600cm ^-1 (w), 515cm ^-1 (W) Moreover, the optical rotation of the obtained product is shown below.

[Α] _D = + 4.48 ° (27 ° C., C = 1, chloroform solution) Example 3 (R) -4- (6 ″ -chloro-4 ″ -methyldecyloxy) -4′-hexyloxybiphenyl Synthesis [α] _D = −3.94 ° (27 ° C., C = 1, chloroform solution) of (R) -4- (6 ″ -chloro-4 ″ -methyldecyloxy) -4′-hydroxybiphenyl and n- Synthesis was performed in the same manner as in Example 1 except that hexyl bromide was used to obtain a white powder having a melting point of 74.8 ° C.

As a result of infrared spectroscopic analysis, the obtained product had the following characteristic absorption, and the desired (R) -4- (6 ″ -chloro-4 ″) was obtained.
-Methyldecyloxy) -4'-hexyloxybiphenyl was confirmed.

^{3040cm -1 (vw), 2940cm -1} (s), 2870cm -1 (s), 1605cm -1 (s), 1565cm -1 (vw), 1500cm -1 (s), 1465cm -1 (s), 1390cm ^{-1 (m), 1325cm -1 (} vw), 1270cm -1 (s), 1245cm -1 (s), 1180cm -1 (m), 1130cm -1 (w), 1040cm -1 (m), 1000cm - ¹ (w), 935cm ^-1 (w), 820cm ^-1 (s), 730cm ^-1 (vw), 660cm ^-1 (vw), 600cm ^-1 (w), 515cm ^-1 (w) The optical rotation of the product is shown below.

[Α] _D = + 0.21 ° (24 ° C, C = 1, chloroform solution)

Claims (1)

[Claims] 1. An optically active biphenyl ether compound represented by the following general formula (I). (In the formula, R ₁ represents a linear alkyl group having 1 to 18 carbon atoms, R ₂ represents a hydrogen atom or an alkyl group having 1 to 11 carbon atoms, and * represents an asymmetric carbon atom.)