Crystal structures of two isomeric oximes. (EE)-2-methyl-3-phenyl-3-thiocyanatopropenaldoxime and (Z)-5-methyl-6-phenyl-1,3-thiazin-2-one oxime

The crystal structure of two isomeric oximes, C₁₁N₁₀N₂OS have been studied by X-ray diffraction. The open-chain thiocyanato derivative is somewhat'less dense and crystallizes with the orthorhombic space group Pbcn;a,b,c=18.718(1), 10.601(3), 11.528(1) Å,Z=8. The heterocyclic isomer occurs as pseudo-orthorhombic (Cmma)twinned crystals of space group P2₁/n, a, b, c, =12.11(1), 7.46(1), 12.12(1) Å, 100.09(1)^o,Z=4. Twinning occurs as a result of the near-equality of the monoclinica andc cell constants.