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Patent US4973429 - Organic materials with non-linear optical properties - Google Patents
A material in the form of a film is described which contains, in an orientated arrangement which does not display point symmetry, compounds of formula I ##STR1## wherein X is ═CH-- or ═N--, R1 is C12 -C30 -alkyl, R2 is hydrogen or C1 -C30 -alkyl, R3 is --NO2, --CN, --CF3, --COCF3, --SO2 CH3 or --SO2...http://www.google.com/patents/US4973429?utm_source=gb-gplus-sharePatent US4973429 - Organic materials with non-linear optical properties
Publication number US4973429 A
Application number US 07/311,482
Also published as EP0329613A2, EP0329613A3
Publication number 07311482, 311482, US 4973429 A, US 4973429A, US-A-4973429, US4973429 A, US4973429A
Inventors Gero Decher, Bernd Tieke, Christian Bosshard, Peter Gunter
Patent Citations (21), Non-Patent Citations (31), Referenced by (61), Classifications (34), Legal Events (5)
Organic materials with non-linear optical properties
US 4973429 A
P=χ.sup.(1) ·E+χ.sup.(2) ·E.sup.2 +χ.sup.(3) ·E.sup.3 +. . .
A very wide variety of substrates with a microscopically planar surface are suitable as solid supports for the LB process. Examples are metals such as aluminium, copper, silver or gold, semiconductors such as germanium, silicon or GaAs, inorganic materials such as glass, quartz, KNbO3, LiNbO3, ZnSe or Si2 N3, or plastics such as Teflon®, polyethylene, polypropylene, polymethyl methacrylate or polyesters. It is also possible to use supports which have been rendered hydrophobic, for example glass or quartz which has been pretreated with trichloromethylsilane, dichlorodimethylsilane or trichlorooctadecylsilane.
(A) PREPARATIVE EXAMPLES Example 1: Synthesis of 2-hexadecylamino-5-nitropyridine 1
0.5 g (3.2 mmol) of 2-chloro-5-nitropyridine (Fluka, purum), 0.76 g (3.2 mmol) of hexadecylamine (Merck-Schuchard, for synthesis) and 1 g of NaHCO3 are weighed out and suspended in 10 ml of CHCl3 /DMF 1:1 (puriss., for analysis). The suspension is heated to 100° C. (bath temperature) and stirred for 4 hours at this temperature. When the reaction mixture has cooled, water is added and extraction is carried out with diethyl ether. The organic phase is extracted twice with water and dried over Na2 SO4. After evaporation of the solvent, the residue is chromatographed on 50 times the amount of silica gel (eluent=hexane/ether 95:5). The slightly yellowish product fraction is concentrated and 1 is recrystallized again from hexane/ether.
This yields 0.94 g of yellowish crystals (81%) melting between 76° and 78° C.
This yields, after chromatography, 0.64 g of yellowish crystals (46% of theory) melting at 74°-77° C. The elemental analysis data of 7 are listed in Table 2.
This yields, after chromatography, 1.70 g of yellow crystals (88% of theory) melting at 65°-68° C. The elemental analysis data of 8 are listed in Table 2.
This yields, after chromatography, 0.96 g of yellow crystals (43% of theory) melting at 36°-41° C. The elemental analysis data of 9 are listed in Table 2.
The procedure is as described under Examples 2-6, 2-chloro-5-nitropyridine being reacted with N-methyldocosylamine. The yield is 69% of theory. The product melts at 88°-90° C. The elemental analysis data of 10 are listed in Table 2.
This yields 0.78 g (62% of theory) of yellow crystals melting at 78°-80° C. The elemental analysis data of 11 are listed in Table 3.
This yields, after chromatography, 0.93 g of light yellow crystals (66% of theory) melting at 58°-59° C. The elemental analysis data of 12 are listed in Table 3.
This yields, after chromatography, 1.12 g of yellow crystals (50% of theory) melting at 40°-42° C. The elemental analysis data of 13 are listed in Table 3.
This yields 1.65 g (71% of theory) of a yellowish orange waxy substance melting at 53°-56° C. The elemental analysis data of 16 are listed in Table 3.
The procedure is as described under Examples 14-15, 2,4-dinitro-5-fluoroaniline being reacted with N-methyldocosylamine. The yield is 48% of theory. The product melts at 87°-89° C. The elemental analysis data of 17 are listed in Table 3.
The crude product (1.05 g) is recrystallized twice from ethanol and filtered on silica gel (ether/hexane). This yields 0.47 g of colourless to slightly yellowish crystals melting at 73°-75° C.
The synthesis is carried out analogously to Example 18 using docosylamine as the amine. This yields 0.57 g of colourless to slightly yellowish crystals melting at 75°-77° C.
The synthesis is carried out analogously to Example 18 using tetracosylamine as the amine. This yields 0.32 g of colourless to slightly yellowish crystals melting at 89°-90° C.
(B) PRODUCTION OF MONOLAYERS AND MULTILAYERS BY THE LB TECHNIQUE Example 21: Production of monolayers at the gas/water interface
Monolayers are produced at the gas/water interface using a preparative Lauda film balance. The high-purity water required is freshly prepared with a Milli-Q unit from Millipore. The monomolecular film is produced by allowing drops of a fresh spreading solution (concentration of the amphiphile in CHCl3 (Merck-Uvasol)=1±0.5 mg/ml) to fall onto the water surface according to standard techniques. Each time after the solvent has evaporated, force/area diagrams are recorded at different temperatures (compression rate=12.3 cm2 /min). The characteristic data determined are the collapse pressure Fc and the collapse area Ac of the monolayer at the relevant temperature (see Table 4).
The procedure for producing monolayers of mixtures of amphiphiles is as described under Example 21. A common solution of two or more amphiphiles of defined composition is used as the spreading solution (total concentration of the amphiphiles in CHCl3 (Merck-Uvasol)=1±0.5 mg/ml). The composition and characteristic data of these monolayers are listed in Table 5.
On a subphase of pure water at a temperature of 20° C., a monomolecular layer of compound 14 is produced, analogously to Example 21, on a NIMA film balance for alternating layers and compressed to a film pressure of 30 mN/m. A glass support which has been rendered hydrophobic with octadecyltrichlorosilane is then dipped vertically through the monolayer into the subphase at a speed of 10 mm/min.
TABLE 1______________________________________Characteristic data of the 2-alkylamino-5-nitropyridines 1-6 prepared ##STR3##Sub-stance R.sub.1  Melting point                     C,H,N calc.                               C,H,N found______________________________________1     C.sub.16 H.sub.33          76-78°                     % C 69.38 % C 69.33                     % H 10.26 % H 10.18                     % N 11.56 % N 11.472     C.sub.18 H.sub.37          66-69°                     % C 70.55 % C 70.26                     % H 10.55 % H 10.43                     % N 10.73 % N 10.613     C.sub.20 H.sub.41          80-82°                     % C 71.55 % C 71.43                     % H 10.81 % H 10.96                     % N 10.01 % N  9.924     C.sub.22 H.sub.45          82-85°                     % C 72.43 % C 72.62                     % H 11.03 % H 11.07                     % N  9.39 % N  8.965      C.sub.24 H.sub.49          85-88°                     % C 73.21 % C 73.32                     % H 11.23 % H 11.39                     % N  8.83 % N  8.576     C.sub.26 H.sub.53          88-90°                     % C 73.90 % C 74.29                     % H 11.40 % H 11.59                     % N  8.34 % N  7.97______________________________________
TABLE 2__________________________________________________________________________Characteristic data of the alkylaminonitropyridines 7- 10prepared ##STR4##               Melting               pointSubstance R.sub.1      R.sub.2           R.sub.3               [°C.]                    C,H,N calc.                           C,H,N found__________________________________________________________________________7     C.sub.18 H.sub.37      H    NO.sub.2               74-77                    % C 63.27                           % C 63.45                    % H  9.24                           % H  9.15                    % N 12.83                           % N 12.848     C.sub.18 H.sub.37      C.sub.18 H.sub.37           H   65-68                    % C 76.46                           % C 76.38                    % H 12.05                           % H 11.97                    % N  6.52                           % N  6.559     C.sub.18 H.sub.37      C.sub.18 H.sub.37           NO.sub.2               36-41                    % C 71.46                           % C 71.25                    % H 11.12                           % H 11.01                    % N  8.13                           % N  8.2610    C.sub.22 H.sub.45      CH.sub.3           H   88-90                    % C 72.84                           % C 72.57                    % H 11.13                           % H 11.09                    % N  9.10                           % N  9.03__________________________________________________________________________
TABLE 3__________________________________________________________________________Characteristic data of the nitro-N-alkylanilines 11- 17prepared ##STR5##                   M.p.Substance R.sub.1      R.sub.2           R.sub.3               R.sub.5                   [°C.]                        C,H,N calc.                               C,H,N found__________________________________________________________________________11    C.sub.18 H.sub.37      H    H   H   78-80                        % C 73.80                               % C 73.75                        % H 10.84                               % H 10.92                        % N  7.17                               % N  7.1012    C.sub.18 H.sub.37      H    NO.sub.2               H   58-59                        % C 66.17                               % C 66.15                        % H  9.49                               % H  9.53                        % N  9.625                               % N  9.5913    C.sub.18 H.sub.37      C.sub.18 H.sub.37            NO.sub.2               H   40-42                        % C 73.31                               % C 73.13                        % H 11.28                               % H 11.16                        % N  6.11                               % N  6.0914    C.sub.18 H.sub.37      H    NO.sub.2               NH.sub.2                   97-99                        % C 63.97                               % C 63.81                        % H  9.39                               % H  9.30                        % N 12.43                               % N 12.2915    C.sub.22 H.sub.45      H    NO.sub.2               NH.sub.2                   108-110                        % C 66.37                               % C 66.36                        % H  9.95                               % H 10.00                        % N 11.06                               % N 11.0216    C.sub.18 H.sub.37      C.sub.18 H.sub.37           NO.sub.2               NH.sub.2                   63-66                        % C 71.75                               % C 71.60                        % H 11.18                               % H 11.11                        % N  7.97                               % N  7.9517    C.sub.22 H.sub.45      CH.sub.3           NO.sub.2               NH.sub.2                   87- 89                        % C 66.89                               % C 66.32                        % H 10.07                               % H  9.95                        % N 10.76                               % N 10.84__________________________________________________________________________
TABLE 4______________________________________Characteristic data of the monolayers of pure amphiphiles atthe gas/water interface       Monolayers             Temp. ofExample  Substance  the subphase                        F.sub.c A.sub.cno.    no.        [°C.]                        [mN/m]  [nm.sup.2 /mol]______________________________________21a    1          5          11      0.3221b    2          9          20      0.3221c    3          15         29      0.3221d    4          15         39      0.3121e    5          20         46      0.2921f    6          20         54      0.2921g    8          5          18      0.4021h    11         10         8       0.4021i    13         4          8       0.5021j    14         18         49      0.2221k    15         28         50      0.2221l    16         10         47      0.41______________________________________
TABLE 5______________________________________Characteristic data of the monolayers of mixtures of amphi-philes at the gas/water interface          Monolayers                    Temp.Exam-           Molar    of theple             ratio    subphase                           F.sub.c                                  A.sub.cno.   Substances           in %     [°C.]                           [mN/m] [nm.sup.2 /mol]______________________________________22a   methyl    33       20     24     0.26 arachidate (MA) (Fluka, puriss.) and 4     6722b   MA        33       15     31     0.24 and 4     67______________________________________
TABLE 6__________________________________________________________________________Characteristic data of the LB films of pure amphiphiles      Multilayers           Temp. of the  Dipping speed                                 Number of λ.sub.max of theExampleSubstance      F.sub.t           subphase, T   s.sub.1                             s.sub.2                                 double layers                                        d.sub.001 *                                           monolayerno.  no.   [mN/m]           [°C.]                  Substrate                         [mm/min]                                 transferred                                        [nm]                                           [nm]__________________________________________________________________________23a  2     9    9      C.sub.18 -glass                         5   10  15     3.7723b  3     12   15     C.sub.18 -glass                         15  30  18     4.11                                           37423c  4     19   15     C.sub.18 -glass                         10  20  18     4.42                                           37423d  5     30   15     C.sub.18 -glass                         20  40  18     4.73                                           37423e  6     27   20     C.sub.18 -glass                         20  60  18     4.98                                           37423f  4     18   15     C.sub.18 -quartz                         10  20  27023g  5     24   20     C.sub.18 -quartz                         10  30  550    4.7323h  4     18   15     C.sub.18 -Si single                         10  20  18     4.36                  crystal23i  4     20   15     ZnSe   10  30  10023j  8     10   5      C.sub.18 -glass                         7.5 12.5                                 10     4.86                                           42423k  14    20   10     C.sub.18 -glass                         7.5 15  20     5.3323l  16    18   15     C.sub.18 -glass                         12.5                             25  20     3.9123m  15    25   28     C.sub.18 -glass                         15  20  1523n  4     18   15     C.sub.18 -quartz                         15  30  5         37423o  4     18   15     C.sub.18 -quartz                         15  30  10        37423p  4     18   15     C.sub.18 -quartz                         15  30  15        37423q  4     18   15     C.sub.18 -quartz                         15  30  30        37423r  4     18   15     C.sub.18 -quartz                         15  30  45        37423s  4     18   15     C.sub.18 -quartz                         15  30  60        37423t  4     18   15     C.sub.18 -quartz                         15  30  90        37423u  4     18   15     C.sub.18 -quartz                         15  30  135       37423v  4     18   15     C.sub.18 -quartz                         15  30  400    4.37                                           374__________________________________________________________________________ *The thickness of a double layer, d.sub.001, is determined by means of Xrays using a Philips powder diffractometer (Cu--K.sub.α radiation).
TABLE 7__________________________________________________________________________Characteristic data of the LB films of mixtures of amphiphiles       MultilayersSubstances of                     Number of                                      Optical densityExampleExample no.       F.sub.t            Subphase T s.sub.1                          s.sub.2                             layers                                   d.sub.001 *                                      per layerno.  (see Table 5)       [mN/m]            [°C.]                  Substrate                       [mm/min]                             transferred                                   [nm]                                      (at λ.sub.max)__________________________________________________________________________25a  22b    18   15    C.sub.18 -glass                       20 60 18    5.16                                      0.0048                                      (370 nm)__________________________________________________________________________ *The thickness of a double layer, d.sub.001, is determined by means of Xrays (cf. Table 6).
TABLE 8______________________________________Frequency doubling in LB layer systems of pure amphiphiles2-6 (cf. Example 27)  Number of layers              I.sup.2ω (relative to 4.tbd.100)Substance    transferred   II*         ⊥*______________________________________2        36            5           0.53        36            52          54        36            100         55        36            12          0.56        36            6           0.2______________________________________ *Light vector parallel or perpendicular to the direction of dipping
TABLE 10______________________________________Coupling angles and effective refractive indices for trans-mission in LB multilayers of 4 for different layer thick-nesses (light vector parallel to the direction of dipping)(cf. Example 28)Number of double        Coupling angle                    Effective refractivelayers transferred        [degrees]   index N.sub.eff______________________________________ 50          9.65        1.503100          9.03        1.514180          8.84        1.517______________________________________
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U.S. Classification 252/587, 252/589, 546/346, 546/298, 252/582, 546/307, 546/304, 546/289, 568/924, 546/315, 546/286, 546/310, 546/288, 546/313
International Classification G02F1/35, C07D213/74, G02F1/361, C07C255/58, G02F1/355, C07C225/22, C07C67/00, C07C209/00, H01S3/108, C07C211/52
Cooperative Classification B82Y20/00, C07D213/74, G02F1/3618, C07C225/22, C07C211/52
European Classification B82Y20/00, C07C211/52, G02F1/361L, C07C225/22, C07D213/74
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:DECHER, GERO;TIEKE, BERND;BOSSHARD, CHRISTIAN;AND OTHERS;REEL/FRAME:005432/0878;SIGNING DATES FROM