CRYSTAL AND MOLECULAR STRUCTURE OF 3-HYDROXY-5-PHENYLISOXAZOLE (ALPHA-FORM)

The crystal structure of the α form of 3‐hydroxy‐5‐phenylisoxazole has been determined from three‐dimensional X‐ray data. The crystals are monoclinic, space group P21/n with four molecules in the unit cell. The cell dimensions are: a = 10.41(2); b = 3.89(1); c = 19.14(4) Å; β = 96.1° (3). The structure was refined by the block‐diagonal least‐squares method to a final R value of 0.080 for 1111 observed reflections. The molecular dimensions are in good overall agreement with those in β form, while the packing is markedly different. Conjugation and planarity in the molecule are discussed. Copyright © 1969 Journal of Heterocyclic Chemistry