X-RAY STUDIES OF THE INTRAMOLECULAR AND INTERMOLECULAR H-BONDING IN 2PHENOLIC MANNICH-BASES

The crystal structures of two phenolic Mannich bases. rachloro-6-hydro xy)phenyl]-N,N-dimethylmethanamine (1) and 1-[(3-nitro-6-hydroxy)pheny l]-N. N-diisobutylmethanamine (2), were determined by using the single crystal X-ray diffraction method. The results and conditions for mole cule 1. C9H9NOCl4, are: M(r) = 288.99, monoclinic, C2/c, a = 21.88(2) angstrom, b = 8.419(7) angstrom, c = 14.63(1) angstrom, beta = 119.62( 4)-degrees, V = 2344(3) angstrom3, Z = 8. D(calc) = 1.638 g cm-3, lamb da(MoKalpha) = 0.71069 angstrom, mu = 9.87 cm-1, F(000) = 1168, T = 29 6 K, R = 0.043 for 1559 observed reflections. For molecule 2, C15H24N2 O3, results and conditions are: M(r) = 280.37, orthorhombic, P2(1)2(1) 2(1), a = 8.850(7) angstrom, b = 29.399(6) angstrom, c = 6.22(1) angst rom, V = 1620(4) angstrom3, Z = 4, D(calc) = 1.150 g CM-3, lambda(MoKa lpha) = 0.71069 angstrom, mu = 0.75 cm-1, F(000) = 608, T 296 K, R 0.0 62 for 755 observed reflections. Compound 1 was determined to have int ermolecular hydrogen bonding involving the zwitterionic form N+-H...O- . For compound 2 intramolecular H-bonding was observed with the N ... H 0 form retained. Complementary IR measurements in the solid state we re in good agreement with the X-ray results. The geometry of the hydro gen bond present depends on the substituents at the amine nitrogen ato m.