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Hydrothermal (deuteratothermal) reaction of L-ethyl lactate (Lig-Et) with Eu(ClO(4))(3)6 H(2)O gives colorless block crystals of [Eu(Lig)(2)(X(2)O)(2)][ClO(4)] (1, X=H; 2, X=D) both of which possess a two-dimensional laminar homochiral framework. Single-crystal dielectric measurements reveal that 1 and 2 display a giant dielectric anisotropy approximately exceeding 100 and large isotopic effect with about 54 % enhancement along the a axis. Their ferroelectric features further confirm this respect. Crystal parameters: 1, C(6)H(14)ClO(12)Eu, M(r)=465.58, monoclinic, C(2), a=8.6786(6), b=8.3965(6), c=10.2153(7) A, beta=92.040(1) degrees , V=743.92(9) A(3), Z=2, rho(calcd)=2.079 Mg m(-3), R(1)=0.0508, wR(2)=0.1239, mu=4.448 mm(-1), S=1.043; Flack=0.04(5). 2: C(6)H(10)D(4)ClO(12)Eu, M(r)=469.61, monoclinic, C(2), a=8.689(2), b=8.410(2), c=10.224(3) A, beta=92.057(4) degrees , V=746.7(3) A(3), Z=2, rho(calcd)=2.089 Mg m(-3), R(1)=0.0465, wR(2)=0.1150, mu=4.432 mm(-1), S=1.058; Flack=0.02(5).

Colorless block crystals of MOF (metal-organic framework) 1 and 2 were prepared in respective yields of 65 and 60% by thermal treatment of HQA (HQA=6-methoxyl-(8S,9R)-cinchonan-9-ol-3-carboxylic acid) with ZnBr(2) in either H(2)O or D(2)O and 2-butanol at 70 degrees C for 1-2 days. The MOFs 1 and 2 are isostructural, one-dimensional chains in which the local coordination geometry around the Zn center can be best described as a slightly distorted tetrahedron defined by two bromine atoms, one nitrogen atom of quinoline from HQA, and an oxygen atom of carboxylate from HQA. The nitrogen atom of the quinuclidine of HQA is protonated in a zwitterionic form. The MOFs 1 and 2 crystallize in a polar point group (C(2), space group P2(1)) which belongs to ferroelectric active compounds. MOFs 1 and 2 display both ferroelectric behavior and large dielectric constants. Interestingly, at low frequency range the dielectric response to water can achieve an approximate increase of more than 600%. Crystal parameters: 1: C(20)H(28)Br(2)NO(7)Zn, M=619.62, monoclinic, P2(1), a=9.5711(8), b=12.0486(10), c=11.1972(9) A, alpha=gamma=90, beta=98.4(2) degrees , V=1277.39(18) A(3), Z=2, rho(cald)=1.611 mg m(-3), R(1)=0.0499, wR(2)=0.0982, mu=4.126 mm(-1), S=1.015, Flack value=0.032(13); 2: C(20)H(22)D(6)Br(2)NO(7)Zn, M=625.66, monoclinic, P2(1), a=9.5650(9), b=12.0392(11), c=11.1973(10) A, alpha=gamma=90, beta=98.44(2) degrees, V=1275.5(2) A(3), Z=2, rho(cald)=1.629 mg m(-3), R(1)=0.0543, wR(2)=0.1072, mu=4.133 mm(-1), S=1.056, Flack value=0.025(17).

The molten reaction of 2-naphthol, 4-(aminomethyl)pyridine, and 4-pyridinecarboxaldehyde at about 180 degrees C yields trans-2,3-dihydro-2,3-di(4'-pyridyl)benzo[e]indole (1) which possesses two chiral centers, rather than an expected Betti-type reaction product with only one chiral carbon center. The same reactions, using 3-pyridinecarboxaldehyde, 4-cyanobenzaldehyde, or 3- cyanobenzaldehyde instead of 4-pyridinecarboxaldehyde produce the related compounds trans-2,3-dihydro-2-(4'-pyridyl)-3-(3"-pyridyl)benzo[e]indole (2), trans-2,3-dihydro-2-(4'-pyridyl)-3-(4"-cyanophenyl)benzo[e]indole (3), and trans-2,3-dihydro-2-(4'-pyridyl)-3-(3"-cyanophenyl)benzo[e]indole (4), respectively. This reaction proceeds with a high degree of stereoselectivity with a trans/cis ratio of about 98:2 at elevated temperature. Compounds 1, 2, and 4 crystallize in a noncentrosymmetric space group (Pca2(1), Pca2(1), and Cc), while compound 3 has a chiral space group (P2(1)). These successfully acentric packing arrangements are probably due to the molecule bearing both two chiral centers and potential hydrogen-bonding groups. Furthermore, the reaction of racemic 6-hydroxy-2'-methyl-2-naphthaleneacetic acid with ethyl-2-cyano-1-(4'-pyridyl)acrylic acetate in the presence of piperidine gives 1-pyridyl-2-ethoxycarbonyl-3-amino-1H-naphtho[2,1-b]pyran-2'-methylacetic acid (5), which likewise crystallizes in a chiral space group. All of compounds are second harmonic generation (SHG) active, and have a very strong SHG response approximately about 8.0, 5.0, 12.0, 6.0, and 1.4 (for 1-5 compounds) times that of urea. Ferroelectric property measurements indicate that compounds 1, 2, 4, and 5 may display ferroelectric behavior.

Under hydrothermal (solvothermal) reaction conditions chiral compounds 1, 2, and 3 and one acentric compound 4 were obtained by the reaction of Zn(2+) or Cd(2+) with racemic 3-(3-pyridyl)-3-aminopropionic acid (rac-HPAPA). Compounds 1 and 2 crystallized in chiral space group P2(1)2(1)2(1). At 105 degrees C, racemic 3-pyridyl-3-aminopropionic acid (rac-HPAPA) reacted with Zn(ClO4)(2).6 H2O and dehydrogenated in situ to form the first chiral coordination polymer [Zn[(E)-3-C(5)H4N-C(NH2)=CH-COO]]ClO4 (1) with a beta-dehydroamino acid. Beyond 120 degrees C, the reaction of rac-HPAPA with Zn(ClO4)(2).6 H2O deaminates in situ to form chiral coordination polymer [Zn[(E)-3-C5H4N-CH=CH-COO](OH)] (2). At relatively low temperatures (70 degrees C), the solvothermal reaction of Zn(NO3)(2).6 H2O with rac-HPAPA in methanol does not lead to any change in the ligand and results in the formation of a chiral (P2(1)2(1)2(1)) coordination polymer [Zn(papa)(NO3)] (3). The same reaction of Cd(ClO4)(2).6 H2O with HPAPA also does not lead to any change in ligand and results in the formation of noncentric (Cc) coordination polymer [Cd(papa)(Hpapa)]ClO4.H2O (4). The network topology of both 1 and 3 is 10,3a, while 2 has a diamondoid-like (KDP-like, KDP=potassium dideuterophosphate) network. Particularly interesting from a topological perspective is that 4 has an unprecedented three-dimensional network. Compounds 1, 2, 3, and 4 are all second harmonic generation (SHG) active with 1 exhibiting the strongest response, while only 4 also displays good ferroelectric properties.