π-Facial selectivities in nucleophilic additions to 4-hetero-tricyclo[5.2.1.02,6]decan-10-ones and 4-hetero-tricyclo[5.2.1.02,6]dec-8-en-10-ones: an experimental and computational study
Several endo-tricyclo[5.2.1.02,6]decan-10-ones and endo-tricyclo[5.2.1.02,6]dec-8-en-10-ones with hetero atom modifications at the distal C-4 position have been subjected to hydridereduction. π-Face selectivities in these systems are largely governed by the same electronic factors that were earlier identified in the case of the norbornyl system. A computational study demonstrates good predictability
4-Oxatricyclo[5.2.1.0<sup>2,6</sup>]decan-10-one and 4-Oxatricyclo[5.2.1.0<sup>2,6</sup>]dec-8-en-10-one. Experimental and DFT Investigations of the π-Selectivities
作者:Veejendra K. Yadav、Rengarajan Balamurugan
DOI:10.1021/jo015945t
日期:2002.1.1
Ab initio MO and experimental pi-selectivities of hydride additions to 4-oxatricyclo[5.2.1.0(2.6)]decan-10-one and 4-oxatricyclo[5.2.1.0(2.6)]dec-8-en-10-one are described. The interactions Of sigma(C1-C2) and sigma(C6-C7) with pi*(C=O), on one hand, and those of sigma(C1-C9) and sigma(C7-C8) with pi*(C=O), on the other hand, support anti-selectivities for both. This is in full accordance with the experiments. The arguments that are based on electrostatic interactions and electron donation from the ring oxygen do not apply.