COMPLEXATION WITH DIOL HOST COMPOUNDS .7. STRUCTURES AND THERMAL-ANALYSIS OF 1,1,2,2-TETRAPHENYLETHANE-1,2-DIOL WITH LUTIDINE GUESTS

Structures of the inclusion compounds of 1,1,2,2-tetraphenylethane-1,2-diol with 2,6-lutidine (1), 3,5-lutidine (2) and 3,4-lutidine (3) have been determined. Crystal data: (1) C26H22O2.C7H9N, M(r) = 473.62, triclinic, P1BAR, a = 9.414(7), b = 11.191(4), c = 13.328(18) angstrom, alpha = 82.81(7), beta = 70.78(12), gamma = 86.44(4)-degrees, V = 1315.2 angstrom 3, Z = 2, D(m) = 1.17, D(c) = 1.20 g cm-3, lambda-(Mo-K-alpha) = 0.710 69 angstrom, mu = 0.40 cm-1, F(000) = 504. (2) C26H22O2.(C7H9N)2, M(r) = 580.77, triclinic, P1BAR, a = 12.099(4), b = 17.869(5), c = 17.873(10) angstrom, alpha = 64.65(3), beta = 87.32(4), gamma = 75.25(2)-degrees, V = 3368.4 angstrom 3, Z = 4, D(m) = 1.12, D(c) = 1.15 g cm-3, lambda-(Mo-K-alpha) = 0.710 69 angstrom, mu = 0.64 cm-1, F(000) = 1240. (3) C26H22O2.(C7H9N)2, M(r) = 580.77, triclinic, P1BAR, a = 9.163(4), b = 11.740(4), c = 17.721(7) angstrom, alpha = 69.50(3), beta = 74.22(4), gamma = 73.09(4)-degrees, V = 1677.2 angstrom 3, Z = 2, D(m) = 1.14, D(c) = 1.15 g cm-3, lambda-(Mo-K-alpha) = 0.710 69 angstrom, mu = 0.38 cm-1, F(000) = 620. The final R values at 293 K were (1) 0.043, (2) 0.070 and (3) 0.067 for 3382, 8561 and 4828 unique reflections. Strong host-guest hydrogen bonding is observed in all structures, O ... N distances are between 2.664 and 2.889 angstrom. Thermal analysis revealed the strength of binding of the guest molecules and a competition experiment showed that 3,5-lutidine is preferentially included over 2,6-lutidine.