Structural features of Ortho-hydroxy bis-phenols and their comparison with Para-hydroxy bis-phenols

The crystal structures of four bis-phenols are reported to substantiate the fact that the weak interactions play a major role in the crystal packing of bis-phenols. The reaction of 2,4-dimethylphenol with aldehydes such as 2-naphthaldehyde, terephthaldehyde in the presence of trifluoracetic acid gave 2-[bis(2-hydroxy 3,5-dimethylphenyl)methyl]naphthalene (1) and 4-[bis(2-hydroxy 3,5-dimethylphenyl) methyl]benzaldehyde (2), respectively. The 2-[bis-(2-hydroxy 3,5-dimethylphenyl)-methyl]naphthalene (1) crystallizes in orthorhombic, Pbca, a = 11.905(3) angstrom, b = 18.788(5) angstrom, c = 18.894(5) angstrom, 4-[bis(2-hydroxy 3,5-dimethylphenyl)methyl] benzaldehyde (2) in monoclinic, Cc, a = 8.880(3) angstrom, b = 16.394(7) angstrom, c = 13.700(5) angstrom, gamma = 104.542(2)degrees. The reaction of 2-nitrobenzaldehyde with 2,4-dimethylphenol gave 2-benzo[c] isoxazo-3-yl 4,6-dimethylphenol (3) and its crystal parameters are orthorhombic, P2(1)2(1)2(1), a = 7.737(6) angstrom, b = 11.885(9) angstrom, c = 13.336(8) angstrom. The reaction of 2,6-dimethylphenol with 4-nitrobenzaldehyde and 2-chlorobenzaldehyde gave bis(4-hydroxy 3,5-dimethylphenyl)(4-nitrophenyl)methane (4) and bis(4-hydroxy 3,5-dimethylphenyl)(2-chlorophenyl)methane (5), respectively. The bis(4-hydroxy 3,5dimethylphenyl)(4-nitrophenyl)methane (4) crystallizes in monoclinic, C2/c, a = 25.921(1) angstrom, b = 12.202(4) angstrom, c = 15.6084(7) angstrom, beta = 122.172(4)angstrom, and bis(4-hydroxy 3,5-dimethylphenyl) (2-chlorophenyl)methane crystallizes as acetonitrile solvate (5) in triclinic, P-1, a = 12.314(3) angstrom, b = 14.111(3) angstrom, c = 15.078(5) angstrom, alpha = 98.268(2)degrees, beta = 111.268(2)degrees, gamma = 114.304(1)degrees. The unit cell of 5 contains two pairs of crystallographically unsymmetric molecules of bis-phenols.