Crystal Structures of Three Organic Adducts Produced by N6-Benzyladenine, Trichloroacetic Acid, 3-Nitrophthalic Acid, and Citric Acid

Three organic adducts of N-6-benzyladenine have been prepared with trichloroacetic acid, 3-nitrophthalic acid, and citric acid. The three crystalline complexes were characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. Compound 1 crystallizes in the triclinic, space group P-1, with a = 5.4634(4) angstrom, b = 9.7180(7) angstrom, c = 15.9707(12)angstrom, alpha = 84.2100(10)degrees, beta = 86.633(2)degrees, gamma = 78.0640(10)degrees, V = 824.75(10) angstrom(3), Z = 2. Compound 2 crystallizes in the triclinic, space group P-1, with a = 7.4065(7) angstrom, b = 8.1151(8) angstrom, c = 18.4782(15) angstrom, alpha = 95.3190(10)degrees, beta = 90.7750(10)degrees, gamma = 115.063(2)degrees, V = 1000.00(16) angstrom(3), Z = 2. Compound 3 crystallizes in the triclinic, space group P-1, with a = 5.0883(5) angstrom, b = 13.0295(11) angstrom, c = 16.4332(14) angstrom, alpha = 69.1550(10)degrees, beta = 83.900(3)degrees, gamma = 79.244(2)degrees, V = 999.35(15) angstrom(3), Z = 2. In 1, the N-9 atom was protonated, thus 1 is a salt. For 2 and 3, all carboxyl groups remain protonated, so 2 and 3 are both cocrystal. These structures adopted homo or hetero supramolecular synthons or both. Analysis of the crystal packing of 1-3 displays that there are O-H center dot center dot center dot O, O-H center dot center dot center dot N, N-H center dot center dot center dot O, and N-H center dot center dot center dot N hydrogen bonds as well as C-H center dot center dot center dot O, CH2 center dot center dot center dot O, C-H center dot center dot center dot Cl, O-O, O-N, Cl center dot center dot center dot N, Cl center dot center dot center dot O, Cl center dot center dot center dot pi, CH2 center dot center dot center dot pi, and pi center dot center dot center dot pi interactions, giving 2D/3D framework structures.