DIREACTIVE MESOGENIC COMPOUNDS AND INTERMEDIATES

Abstract: The invention relates to direactive mesogenic compounds or mixtures thereof comprising mesogene-containing molecule, said mesogens having two side chains attached thereto which contain a terminal polymerizable functional group, said mesogens and said functional groups being separated by at least two to twenty spacer atoms, wherein both spacer groups have different chain length.

Description: DIREACTIVE MESOGENIC COMPOUNDS AND INTERMEDIATES The invention relates to direactive mesogenic compounds or mixtures thereof obtainable by a) treating a mesogenic diol of formula I, HO-MG-OH (0 in which MG is a mesogenic group, with a mixture of the halids of formula II and III, in which Xi and X2 are each independently Cl, Br or J, m and n are different integers between 1 and 20 Ra and R" are each independently groups selected from -CH 2 OH or -CH=CWH wherein W is H, CH 3 or CI, in the presence of a base, and 1 b) treating the resulting intermediate in the case of Ra and R» being -CH 2 OH, with a vinyl derivative of formula CH 2 =CW-(CO) a -0- or a reactive derivative thereof, in which a is 0 or 1 in the case of Ra and R*> being -CH=CWH with a perbenzoic acid. The invention furthermore relates to the preparation of such compounds and to their use in electrooptical scattering systems and for the preparation of oriented liquid crystal polymers. Reactive liquid crystal compounds can be polymerized in situ, whilst in their liquid crystal phase, to give highly crosslinked anisotropic films which can be used, for example, as polarizing beam splitters (see, for example, EP 0,428,213). Reactive liquid crystal compounds have furthermore been proposed for electrooptical scattering systems (see, for example, EP 0,451 ,905), cholesteric polarizers (e.g. EP 0,606,940) and compensation films for STN displays (e.g. EP 0,423,881 ). Reactive liquid crystal di esters of formula are mentioned in EP 0,261 ,712 (n=o), EP 0,331 ,233 (n=1 ). Reactive liquid crystal biphenyls of formula are disclosed by EP 0,405,713. The International Patent application WO 93/22397 discloses a compound of formula These reactive liquid crystalline compounds often exhibit, however, rather high melting points disadvantageous values of the birefringence and comparable narrow mesophase ranges. In view of the broad range of applications of reactive liquid crystal compounds it was desirable to have available further compounds of this type which fulfill the various requirements such as a reasonably low melting point, a high birefringence, a broad mesogenic range and preferably an enantiotropic nematic range to a high degree. It was an object of the present invention to provide new reactive liquid crystalline compounds with advantageous properties thus extending the pool of reactive liquid crystal compounds available to the expert. Other objects of the present invention can be taken from the following detailed specification. The present invention thus relates to reactive mesogenic compounds or mixtures thereof obtainable by treating mesogenic diols of formula I, in particular those having a symetric structure unit with a mixture of halides of formula II and III and to their use in electrooptical systems of scattering type and for the preparation of oriented liquid crystal polymers. The invention furthermore relates to the preparation of compounds according to formula I. Preferred embodiments of the present invention are: a) Composition of direactive compounds comprising at least one compound of each formula IV, V and VI, R , -(CH 2 ) m -O-MG-O-(CH 2 )n-R 2 IV RMCH 2 ) m -O-MG-0-(CH 2 ) m -R * V R 2 -(CH 2 )„-O-MG-0-(CH 2 ) n -R2 VI in which MG, m and n have the meaning given, and R' and R2 are each independently y^ -CH 2 -O-(C0) a -CW=CH 2 or -CH CHW . b) Direactive compound or mixture thereof in which m - n ≥ 1 , in particular 2, 3 or 4. c) Direactive compound or mixture thereof in which MG is a mesogenic group of formula VII, -(A i -Z i )o-A 2 - VIII in which A' and A2 are each independently (a) 1 ,4-phenylene in which one or two CH groups may be replaced by N; (b) 1 ,4-cyclohexyIene in which one or two non- adjacent CH 2 groups may be replaced by -O- or one -CH- group may be replaced by -C(CN)-; r (c) naphthaline-2,6-diyl; it being possible that group (a) is substituted by halogen cyano or alkyl, alkoxy or alkanoyl with 1 to 6 C atoms, Z i is each independently -COO-, -0-CO-, -CH 2 -CH r , -C≡C-, -CH 2 0-, -OCH 2 - or a single bond, and o is 1 , 2 or 3. 10 15 20 25 30 Direactive compound or mixture thereof in which MG is selected from the structure elements (1) to (6). in which is CH 3 , Cl, F, OCH 3 or -CO-CH 3 , and is O, 1 , 2 or 4. β) Direactive compound or mixture thereof in which n and m are given by the following table: m 5 5 5 4 4 n 2 3 4 2 3 A further aspect of the present invention are direactive compounds of formula IV A R 1 -(CH 2 ) m O-MG-0-(CH 2 ) n -R2 (IVA) in which Ri and R have the meaning given, m and n are different integers between 2 and 10, and MG is a mesogenic group, the core of which being symmetrical, preferably a structure element of formula (1), (5) or (6), in particular direactive compounds of the formula IVA1 IVA1 in which R 1 . R 2 . L and r have the meaning given, m and n are different integers between 2 and 10, and t is O or l. Another aspect of the invention are the polymers prepared by polymerizing a monomer according to any of the preceding claims and a chemical intermediate compounds or mixtures thereof useful in preparing direactive compounds or mixtures thereof according to any of the claim 1 to 8, comprising mesogene-containing molecules, said mesogenes having two side chains attached thereto that contain hydroxyl or vinyl group at the end thereof, said mesogenes and said functional groups being separated by at least two to twenty spacer atoms, wherein both spacer groups have different chain length. Above and below, the term reactive mesogenic compounds refers to reactive rod-like molecules which may be enantiotropic, monotropic or isotropic, preferably, however, enantiotropic or monotropic. in the inventive compounds in which MG is a mesogenic group of formula VIII, Ai and A2 can be independently from each other an unsubstituted or a substituted 1 ,4-phenylene group of formula X2, X3, X5 and X6 can be independently from each other H, F, Cl, methyl or CN. In the following, for the sake of simplicity, the following notation will be used: Phe. 2 X 2 3 X 3 5 X 5 6 X 6 is a 1 ,4-phenylene group carrying in 2-position the group X 2 , in 3-position the group X 3 etc.; in case X 2 , X 3 , X 5 and or X 6 , denote H, this will not be specified in above notation, i.e. only true substitutions will be listed. Thus Phe, for example, is an unsubstituted 1 ,4- phenylene group while Phe.2F 5 Cl is a 2-fluoro-5-chloro-1 ,4-phenylene group. Furthermore, Pyr is pyrimidine-2,5-diyl, Pyd is pyridine -2,5-diyl and Nap is a naphthalene-2,6-diyl group. The notation Pyr and Pyd in each case include the 2 possible positional isomers. The compounds according to formula IV comprise 2- and 3-ring compounds (n=1 or 2) of formula IV2 and IV3: R 1 -(CH 2 ) m -0-Ai-Zi-A2-0-(CH 2 ) n -R2 IV2 Ri(CH 2 ) m -0-Ai-Z'-Aι-Zι-A2-0-(CH 2 ) n -R2 IV3 In the 3-ring compounds of formula IV3, the ring groups A' can be chosen independently from each other. Especially preferred is a smaller group of 2-ring compounds exhibiting the following structures for -A'-Z'-A2-: -Phe.2CH 3 -Phe- IV2-1 -Phe.3CH 3 -Phe- IV2-2 -Phe.2CI-Phe- IV2-3 -Phe.3CI-Phe- IV2-4 -Phe.2CN-Phe- IV2-5 -Phe.3CN-Phe- IV2-6 -Phe.2CI3CI-Phe- IV2-7 -Phe.2CI3F-Phe- IV2-8 -Phe.2F-Phe- IV2-9 -Phe.3F-Phe- IV2-10 -Phe.-Phe- IV2-11 -Phe.F-Nap- IV2-12 -Phe.2CI-Nap- IV2-13 -Phe.F-Nap- IV2-14 -Phe.3CI-Nap- IV2-15 -Phe.2F-Pyr- IV2-16 -Phe.2F-Pyr- IV2-17 -Phe.2CH 3 -Pyd- IV2-18 -Phe.2CI-Pyd- IV2-19 -Phe.F-CH2CH2-Phe- IV2-20 -Phe.3F-CH 2 CH r Phe- IV2-21 -Phe.2CI-CH 2 CH 2 -Phe- IV2-22 -Phe.3CI-CH 2 CH r Phe- IV2-23 -Phe.2CN-CH 2 CH r Phe- IV2-24 -Phe.3CN-CH 2 CH 2 -Phe- IV2-25 -Phe.2CI3CI-CH 2 CH r Phe- IV2-26 -Phe.2CI3F-CH 2 CH r Phe- IV2-27 The 3-ring compounds according to formula IV3 preferably exhibit the following structures for -A1-Z1-A1-Z1-A2: U In these structures, IV3-a to IV3-d, L * and L∑ denote independently from each other H, -Cl, -F, -CN and and , in particular, -Cl, -F, -CN, -CH 3 , and/or -(^Hs. Especially preferred are the following patterns: -Phe-Phe.2CH 3 -Phe- IV3-a-1 -Phe-Phe.2CI-Phe- IV3-a-2 -Phe-Phe.2CN-Phe- IV3-a-3 -Phe-Phe.2F-Phe- IV3-a-4 -Phe-Phe-Phe- IV3-a-5 -Phe-Phe.2C 2 H r Phe- IV3-a-6 -Phe-Phe.3CH 3 -Phe- IV3-b-1 -Phe-Phe.3CI-Phe- IV3-b-2 -Phe-Phe.3CN-Phe- IV3-b-3 -Phe-Phe.3F-Phe- IV3-b-4 • Phe-Phe.SCzHs-Phe- IV3-b-5 -Phe.3F-Phe.3CI-Phe- IV3-b-6 ■ Phe.3F-Phe.3CH 3 -Phe- IV3-b-7 -Phe.3CI-Phe.3CI-Phe- IV3-b-8 -Phe.3CI-Phe.3CH 3 -Phe- IV3-b-9 -Phe-Phe.2CI-Phe.3CI- IV3-b-10 -Phe-Phe.3CI-Phe.3CI- IV3-b-11 -Phe-Phe.2CI-Phe.2CI- IV3-b-12 -Phe-Phe.3CI-Phe.2CI- IV3-b-13 -Phe-Phe.2CH 3 -Phe.3CI- IV3-b-14 -Phe-Phe.3CH 3 -Phe.3CI- IV3-b-15 -Phe-Phe.2CH 3 -Phe.2CI- IV3-b-16 -Phe-Phe.3CH 3 -Phe.2CI- IV3-b-17 -Phe-Phe.2F-Phe.3CI- IV3-b-18 -Phe-Phe.3F-Phe.3CI- IV3-b-19 -Phe-Phe.2F-Phe.2CI- IV3-b-20 -Phe-Phe.3F-Phe.2CI- IV3-b-21 -Phe-Phe.2CI-Phe.3CN- IV3-b-22 -Phe-Phe.3CI-Phe.3CN- IV3-b-23 -Phe-Phe.2CI-Phe.2CN- IV3-b-24 -Phe-Phe.3CI-Phe.2CN- IV3-b-25 -Phe-Phe.2CH 3 -Phe.3CN- IV3-b-26 -Phe-Phe.3CH 3 -Phe.3CN- IV3-b-27 -Phe-Phe.2CH 3 -Phe.2CN- IV3-b-28 -Phe-Phe.3CH 3 -Phe.2CN- IV3-b-29 -Phe-Phe.3F-Phe.3CN- IV3-b-30 -Phe-Phe.2F-Phe.3CN- IV3-b-31 -Phe-Phe.3F-Phe.2CN- IV3-b-32 -Phe-Phe.2F-Phe.2CN- IV3-b-33 -Phe-Phe.2F-Phe.2F- IV3-b-34 -Phe-Phe.3F-Phe.3F- IV3-b-35 -Phe-Phe.2CH 3 -C 2 H 4 -Phe- IV3-C-1 -Phe-Phe.2CI-C 2 H 4 -Phe- IV3-C-2 -Phe-Phe.2CN-C 2 H 4 -Phe- IV3-C-3 -Phe-Phe.2F-C 2 H 4 -Phe- IV3-C-4 -Phe-Phe.2C 2 H r C 2 H 4 -Phe- IV3-C-5 -Phe-Phe.2CI3F-C 2 H 4 -Phe- IV3-C-6 -Phe-Phe.2CI3CI-C 2 H 4 -Phe- IV3-C-7 -Phe-C 2 H 4 -Phe.2CH 3 -C 2 H 4 -Phe- IV3-C-8 -Phe-C 2 H 4 -Phe.2CI-C 2 H 4 -Phe- IV3-C-9 -Phe-C 2 H 4 -Phe.2CN-C 2 H 4 -Phe- IV3-C-10 -Phe-C 2 H 4 -Phe.F-C 2 H 4 -Phe- IV3-C-11 -Phe-C 2 H4-Phe.20CF 3 -C 2 H 4 -Phe- IV3-C-12 -Phe-COO-Phe.OCO-Phe- IV3-d-1 -Phe-COO-Phe.2CH 3 -OCO-Phe- IV3-d-2 J . -Phe-COO-Phe.3CH 3 -OCO-Phe- IV3-d-3 -Phe-COO-Phe.2CH 3 3CH 3 -OCO-Phe- IV3-d-4 -Phe-COO-Phe.20CH 3 -OCO-Phe- IV3-d-5 -Phe-COO-Phe.2CI-OCO-Phe- IV3-d-6 -Phe-COO-Phe.2F-OCO-Phe- IV3-d-7 -Phe-COO-Phe.2F3F-OCO-Phe- IV3-d-8 -Phe-COO-PhePhe- IV3-e-1 -Phe-COO-Phe.2FPhe- IV3-e-2 -Phe-COO-Phe.3FPhe- IV3-Θ-3 -Phe-COO-PhePhe.2F- IV3-e-4 -Phe-COO-PhePhe.3F- IV3-Θ-5 -Phe.2F-COO-PhePhe- IV3-e-6 -Phe.3F-COO-PhePhe- IV3-e-7 It was observed that the stability of 3- ring compounds wherein one of the 2 groups Zi is -COO- or -OCO- while the other denotes a single bond, can be increased if the compound is laterally di- or higher substituted, particularly di-substituted by -Cl, -F, -CN and/or -CH 3 . Compounds of this type are preferred. Especially preferred are further 3-ring compounds where both groups Zi are either -COO-, or -OCO- and at least one of the rings Ai, A' * and A2 are at least mono substituted. In the compounds of formula IV Ri is CH 2 = CW-COO-CH 2 -, CH 2 = O / \ CH-0-CH 2 -, HW-C-C-, with W being H, Cl or alkyl with 1-5 C atoms and m being 1 -7. Preferably, R * and R is a vinyl group, an acrylate group, an epoxy group and especially preferred are the following means of R' and R2: CH 2 =CH-COO-CH 2 - Ri-1 CH 3 Cl /°\ R1 - 5 H--C-C- with alkyl denoting d-C 3 -alkyl and m being 1-5. ιs- The reaction methods mentioned are briefly summarized in the following synthetic tree: Scheme I HO-MG-OH 3 , heat HO-(CH 2 ) m 0-MG-0-(CH 2 ) m -OH Λ HO-(CH 2 ) m 0-MG-0-(CH 2 ) n -OH f Mixture HO-(CH 2 ) n 0-MG-0-(CH 2 ) n -OH J 1 ,10-Phenanthroline Mixture of Pd (ll)-Acetate "diacrylates" Mixture of "Divinylethers" DCM = dichloromethane /. Scheme II HO-MG-OH eat Mixture Scheme -* CH 2 =CH-(CH 2 )m-0- • Br Br-(CH 2 ) m -CH_-CH 2 CH 2 =CH-(CH 2 )m-0— ^^- θ\-0-(CH 2 )n-CH=CH 2 /? Certain compounds or mixtures according to the invention are obtainable in a "one-pot-synthesis" as outlined in scheme IV: Scheme (V CI-CH 2 CH 2 -C0 2 -(CH 2 )-.-0-Phe-C0 2 H CI-CH 2 CH 2 -C0 2 -(CH 2 ) n -0-Phe-C0 2 H + H0 ~i ° )~ 0H 1) TFAA/DCM 2) TEA DCM CH 2 =CH-C0 2 -(CH 2 ) m -0-Phe-COO- θVθCO-Phe-0-(CH 2 ) n --OCO-CH=CH 2 CH 2 =CH-C0 2 -(CH 2 ) n -0-Phe-COO— /θVθCO-Phe-0-(CH 2 ) m -OCO-CH-=CH 2 CH 2 =CH-C0 2 -(CH 2 ) n - Phe-COO- θ^-OCO-Phe-0-(CH 2 ) n -OCO-CH=CH 2 TFAA = trifluoroacetic acid TEA = triethylamine Individual compounds of this type can be obtained according to schemes V to VII: Scheme V r^O/H Q HO— o V-OH ► HO— (0V0THP + CI-CH 2 CH 2 -CO 2 -(CH 2 ) m -0-Phe-COOH STEP 1 ^-f Pyridinin PTSA / — ► CICH 2 CH 2 -Cθ 2 -(CH 2 ) m -α e-COO— ( θ )-OH STEP 3 (CH 2 ) n -αPhθ-COOH CH 2 =CH-COO-(CH 2 ) m -0-Phe-COO— ZθVθCO-Phe-0-(CH 2 ) n -OCO-CH=CH- PTSA = p-toluenesulfonate ta Scheme VI CI-CH 2 CH 2 -COO-(CH 2 ), m -o- o}- COOH STEP 2 H 2 /Pd/C CI-CH 2 CH 2 -COO-(CH 2 ) nι -0-/θVcθO— θVθH lo Scheme VII rding to / K 2 C0 3 / butanone mixture of four homologous STEP 2 ride mixture of four homologous The reaction schemes mentioned above are to illustrate the invention without restricting it. The expert can choose other reaction methods without any inventive efforts. In the following and in the preceding, all percentages given are percentages by weight. Temperatures are given in degrees Celsuis. The following examples are intended to illustrate the invention without restricting it. Example 1 The reactive liquid crystalline compound (1) CH 2 =CH-CO 2 -(CH 2 ) 3 -O— /o cOO— ^O^-OCO— ^O^-CHCH^-OCO-CI is prepared via the sequence of reaction steps shown in scheme V. In step 4 of scheme V 2.2 moles TFAA are added dropwise to a solution 2 moles of the phenol obtained in step 3 of scheme V and 2 moles of the benzoic acid in 2 I of DCM. The reaction mixture is stirred at room temperature for 16 hours. Then 5 moles of TEA in 1 I of DCM are added. The mixture is stirred for 16 hours. Aqueous work-up and column chromatography give (1 ) which shows K 111 S. The following compounds are obtained analogously: Compound No. m n phase transition temperatures (°C) (2) 3 (3) 4 (4) 4 5 Comp 1 4 4 K 105 N 164 I Comp 2 5 5 K 91 N 167 I Comp 3 6 6 K 105 (S 95) 152 1 Example 2 A mixture of 1 mol CI-CH 2 CH 2 -COO-(CH 2 ) 4 -0- θ)-COOH, 1 mol CI-CH 2 CH 2 -COO-(CH 2 ) 4 -0-(θ)-COOH , and 1 ™>l p-hydroquinone is treated with 22 moles of TFAA followed by 2.5 moles of TEA. A mixture consisting of 1 part comp 1 and 1 part comp 3 and 2 parts of Compound No. (4) is obtained which shows a melting point of 56 °C and a clearing point of 163 °C. Analogously a mixture of the following compounds is obtained: n m parts 3 3 6 6 3 6 6 3 This composition shows a melting point below 30 °C and a clearing point of 119 °C. Example 3 A mixture of 0.5 moles of biphenol, 1.3 moles of potassium hydroxide, 0.6 moles of 3-bromopropanol and 0.6 moles of 3 bromohexanol is heated in 2 litres of butanone for 16 hrs. After aqueous work-up a mixture of 1 part of HO-(CH 2 ) 3 -0-(0)--(θ -0-(CH 2 ) 3 -OH 2 parts of HO-(CH 2 ) 6 -0-(θ)- 5)-0-(CH 2 ) 3 -OH is obtained. This mixture is treated with 1.2 moles of acryloyl chloride and 1.2 moles of TEA in 1.5 litres of dichloroethane DCM and refluxed for 3 hours. After aqueous work-up the resulting reactionmixture is purified by column- chromatography to yield a mixture of diacrylates (6), (7) and (8). Analogously a mixture of compounds of formulae (9), (10), (11) and (12) is obtained 2Ϋ

Claims: 2r Claims 1. Direactive mesogenic compounds or mixtures thereof obtainable by a) treating a mesogenic diol of formula I, HO-MG-OH (I) in which MG is a mesogenic group, with a mixture of the halids of formula II and III, X-MCHj n-Rb (III) in which X i and X2 are each independently Cl, Br or J, m and n are different integers between 1 and 20 Ra and R> are each independently groups selected from -CH 2 OH or -CH=CWH wherein W is H, CH 3 or CI, in the presence of a base, and b) treating the resulting intermediate - in the case of Ra and R» being -CH 2 OH, with a vinyl derivative of formula CH 2 =CW-(CO) a -0- or a reactive derivative thereof, in which a is 0 or 1 in the case of Ra and R" being -CH=CWH with a perbenzoic acid. 2. Composition of direactive compounds comprising at least one compound of each formula IV, V and VI, R i -(CH 2 ) m -0-MG-0-(CH 2 ) n -R2 IV RMCH 2 ) m -0-MG-0-(CH 2 ) ni -R V R2-(CH 2 ) n -0-MG-0-(CH 2 ) n -R2 VI in which MG, m and n have the meaning given, and Ri and R2 are each independently -CH 2 -0-(CO) a -CW=CH 2 or -CH CHW . Direactive compound or mixture thereof according to claim 1 or 2 in which m - n ≥ 1. 21 4. Direactive compound or mixture thereof according to any of the preceding claim in which MG is a mesogenic group of formula VII, in which Ai and A2 are each independently (a) 1 ,4-phenylene in which one or two CH groups may be replaced by N; (b) 1 ,4-cyclohexylene in which one or two non- adjacent CH 2 groups may be replaced by -O- or one -CH- group may be replaced by -C(CN)-; (c) naphthaline-2,6-diyl; it being possible that group (a) is substituted by halogen cyano or alkyl with 1 to 6 C atoms, Zi is each independently -COO-. -0-CO-, -CH 2 -CH 2 -, -C≡C-, -CH 2 0-, -OCH 2 - or a single bond, and o is 1 , 2 or 3. Z- 5. Direactive compound or mixture thereof according to any of the preceding claims in which MG is selected from in which L is CH 3 , Cl, F, OCH 3 or -CO-CH 3 , and r is 0, 1 , 2 or 4. Direactive compound or mixture thereof according to any of the preceding claims in which n and m are given by the following table: m 5 5 5 4 4 2 3 4 2 3 23 7. Direactive compound of formula IV A R -(CH 2 ) m O-MG-0-(CH 2 ) n -R2 (IVA) in which Ri and R2 have the meaning given, m and n are different integers between 2 and 10, and MG is a mesogenic group, the core of which being symmetrical. 8. Direactive compound according to claim 7 of the formula IVA1 in which R . R 2 , L and r have the meaning given, m and n are different integers between 2 and 10, and t is 0 or 1. 9. Polymers prepared by polymerizing a monomer according to any of the preceding claims. 10. Chemical intermediate compounds or mixtures thereof useful in preparing direactive compounds or mixtures thereof according to any of the claim 1 to 8, comprising mesogene-containing mole¬ cules, said mesogenes having two side chains attached thereto that contain hydroxyl or vinyl group at the end thereof, said mesogenes and said functional groups being separated by at least two to twenty spacer atoms, wherein both spacer groups have different chain length.

Inventors: COATES DAVID, GREENFIELD SIMON, COATES, DAVID, GREENFIELD, SIMON
Applicants: COATES DAVID, GREENFIELD SIMON, MERCK PATENT GMBH, COATES, DAVID, GREENFIELD, SIMON
Application year: 1996
Main classification: C09K19
IPC codes: C07C43, C07C69, C07D303, C08F246, C09K19