T. Sakaki, A. Wakahara, T. Fujiwara
Feb 1, 1975
Citations
0
Influential Citations
6
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
The crystal structure of 5-methoxyindole-3-acetic acid (5-MIAA) has been solved by application of the direct method with symbolic addition procedure. 5-MIAA, colorless transparent prism, is monoclinic, space group C2/c, with lattice parameters: a=34.461(9) A, b=6.150(5) A, c=9.480(5) A, β=96.14(2)°, Z=8. The molecules are hydrogen-bonded into dimers related by the center of symmetry, which are held together in an infinite double-layered sheet structure perpendicular to the a-axis with N–H···O hydrogen bond between indole nitrogen and carboxyl oxygen atoms. The methyl groups of adjacent molecules contact to each other by van der Waals forces. The conformation of the side-chain is quite distinguishable from that of indole-3-acetic acid. The dihedral angle between carboxyl and indole planes is 59.5° in this molecule, whereas that is 90.0° in indole-3-acetic acid, and the carboxyl group sticks out to be perpendicular to the indole plane.