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The gradient-optimized geometry of haloperidol at the 4-21G level

✍ Scribed by C. Van Alsenoy; A. T. H. Lenstra; H. J. Geise

Book ID
102878375
Publisher
John Wiley and Sons
Year
1989
Tongue
English
Weight
577 KB
Volume
10
Category
Article
ISSN
0192-8651

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✦ Synopsis

The molecular structure of haloperidol as free base in its C(13)-Cc( 14) trans form is optimized using Pulay's gradient method and a 4-21G basis set without any geometrical constraints. The resulting structure is compared with the experimental structure of the free base in the C(13)-C( 14) gauche form and with the experimental structure of the HBr salt of haloperidol in the C(13)-C( 14) trans form. Apart from the obvious differences, the two rotameric forms of the free base show many similarities. This, together with the manner in which the differences of the two experimental structures are distributed over the haloperidol molecule, leads to the conclusion that the conspicuous differences between the experimental structures are caused by inaccuracies in the X-ray determination of the HBr salt. Deviations of phenyl ring geometries from D6h symmetry and the asymmetry of the conformation around C(1)-C(9) could be rationalized by intramolecular effects.

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