Crystal structures of two substituted key intermediates of phenothiazine derivatives

The key intermediates, in the synthesis of phenothiazines, 5-hydroxy-5-methyl 3(phenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C17H22O4N2 (I), and 5-hydroxy-5-methyl 3(2'-methylphenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C18H24O4N2 (II), contain essentially substituted cyclohexanone rings in chair conformation with approximately perpendicular oriented phenyl rings. The carbamoyl groups are aligned in opposite directions to facilitate the formation of intramolecular C-H...O interaction and O-H...O hydrogen bonding. The molecules are linked in helical fashion by an N-H...O type intermolecular hydrogen bonding framework. Crystal data: [I], orthorhombic, space group Pbca, a = 9.278(1), b = 19.094(2), c = 19.802(2) Angstrom, V = 3508.0(6) Angstrom(3), Z = 8 and d = 1.206 Mg m(-3), R = 0.074 (wR = 0.137) for 208 parameters and 1190 observed reflections with I greater than or equal to2sigma(I); [II], monoclinic, space group P2(1)/n, a = 10.523(1), b = 9.005(1), c = 19.771(2) Angstrom, beta = 94.96(6)degrees, V = 1866.5(3) Angstrom(3), Z = 4 and d = 1.183 Mg m(-3), R = 0.062 (wR = 0.131) for 217 parameters and 2276 observed reflections with I greater than or equal to2sigma(I).