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Conformation and reactivity of α-oxo-ketenes: Ab initio and semiempirical (AM1, PM3) calculations

✍ Scribed by Rudolf Janoschek; Walter M. F. Fabian; Gert Kollenz; C. Oliver Kappe

Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
803 KB
Volume
15
Category
Article
ISSN
0192-8651

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✦ Synopsis

Ab initio MP2/6-31G*/ /MP2/6-31G* and semiempirical AM1 and PM3 calculations on a series of differently substituted a-0x0-ketenes are used to investigate EIZ-isomerism and rotational barriers in these molecules. Sterically crowded derivatives are found to exist solely as s-E conformers. The unusual stability of these derivatives thus can be attributed to their inability to adopt the s-Z conformation required for the normal a-0x0-ketene reactions.

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