Acta Crystallographica Section C

Crystal Structure Communications

Volume 68, Part 11 (November 2012)

organic compounds

wq3019 scheme

Acta Cryst. (2012). C68, o481-o484    [ doi:10.1107/S0108270112043545 ]

Supra­molecular sheets in (4H-chromeno[4,3-c]isoxazol-3-yl)methanol and its hydrated 8-methyl-substituted analogue at 100 K

P. Rajalakshmi, N. Srinivasan, R. V. Krishnakumar, I. A. Razak and M. M. Rosli

Abstract: The title compounds, (4H-chromeno[4,3-c]isoxazol-3-yl)metha­nol, C11H9NO3, (I), and (8-methyl-4H-chromeno[4,3-c]isoxazol-3-yl)methanol monohydrate, C12H11NO3·H2O, (II), crystallize in the monoclinic space groups P21/c and C2/c, respectively. The simple addition of a methyl substituent in (II) results in a change in the structure type and substantially alters the inter­molecular inter­action patterns, while retaining the point-group symmetry 2/m. Compound (II) crystallizes as a hydrate and the resulting hydrogen-bonding inter­actions involving the water mol­ecule are the cause of differences in the hydrogen-bonded supra­molecular motifs present in (I) and (II). The water mol­ecule in (II) is disordered over two positions having very similar orientations, with occupancies of 0.571 (18) and 0.429 (18), although the pattern of hydrogen-bonding inter­actions for the two disordered water mol­ecules remains essentially the same. In both compounds, the primary donor hy­droxy group adopts a trans conformation with respect to the isoxazole O atom, with a torsion angle of 170.65 (8)° for (I) and 179.56 (10)° for (II), the small difference being due to differences in the hydrogen-bonding environment of the hy­droxy group. In (I), mol­ecules are linked through two independent O-H...N and C-H...O hydrogen bonds and form sheets of centrosymmetric R44(18) and R44(14) rings extending parallel to the (100) plane. The supra­molecular motifs in (II) generate two-dimensional sheets parallel to the (100) plane through a combination of O-H...X (X = N, O) and C-H...O hydrogen bonds, leading to water-assisted noncentrosymmetric R22(8) and R66(20) motifs. The present work is an example of how the simple replacement of a substituent in the main mol­ecular scaffold may transform the structure type, paving the way for a variety of supra­molecular motifs and consequently altering the complexity of the inter­molecular inter­action patterns.

Formula: C11H9NO3 and C12H11NO3·H2O

hkldisplay filedownload file

Structure factor file (CIF format) (179.8 kbytes)
[ doi:10.1107/S0108270112043545/wq3019Isup2.hkl ]
Contains datablock I

hkldisplay filedownload file

Structure factor file (CIF format) (185.1 kbytes)
[ doi:10.1107/S0108270112043545/wq3019IIsup3.hkl ]
Contains datablock II


To open or display or play some files, you may need to set your browser up to use the appropriate software. See the full list of file types for an explanation of the different file types and their related mime types and, where available links to sites from where the appropriate software may be obtained.

The download button will force most browsers to prompt for a file name to store the data on your hard disk.

Where possible, images are represented by thumbnails.

 bibliographic record in  format

  Find reference:   Volume   Page   
  Search:     From   to      Advanced search

Copyright © International Union of Crystallography
IUCr Webmaster