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The Cram Rule Revisited Once More — Revision of the Felkin−Anh Model
Author(s) -
Smith Richard J.,
Trzoss Michael,
Bühl Michael,
Bienz Stefan
Publication year - 2002
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/1099-0690(200208)2002:16<2770::aid-ejoc2770>3.0.co;2-x
Subject(s) - chemistry , selectivity , computational chemistry , transition state , ab initio , gaussian orbital , ab initio quantum chemistry methods , reaction mechanism , organic chemistry , stereochemistry , molecule , catalysis
The reaction mechanism of the LiH addition to α‐chiral ketones and acylsilanes was calculated at the ab initio MP2/6‐311+G**//RHF/6‐31G* level. The selectivities predicted on the basis of the computed transition states and reaction barriers compare well with the experimental data. For compounds possessing very large groups, anti‐Cram selectivity was found; silicon‐containing compounds should show the same types of selectivity as their carbon analogs. The calculations suggest that a revision of the Felkin−Anh model is necessary and a proposal for such a revision is given. (© Wiley‐VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)