Adamantanones nucleophilic addition

The rates of nucleophilic additions to adamantanone have been studied in an attempt to determine the structure of the transition states of nucleophilic additions to carbonyl compounds in general. The kinetic analysis suggests that the transition states of borohydride reductions of ketones are product-like while for bisulfite additions the transition states are reactant-like 367). A similar analysis 36 ) of data obtained for photo-initiated oxetane formation (trans-dicyanoethylene + carbonyl compound) 3681 indicates a reactant-like transition state. 

On p. 1023, it was mentioned that electronic effects can play a part in determining which face of a carbon-carbon double bond is attacked. The same applies to additions to carbonyl groups. For example, in 5-substituted adamantanones (2) electron-withdrawing (-/) groups W cause the attack to come from the syn face, while electron-donating groups cause it to come from the anti face. In 5,6-disubstituted norborn-2-en-7-one systems, the carbonyl appears to tilt away from the 7i-bond, with reduction occurring from the more hindered face. An ab initio study of nucleophilic addition to 4-ferf-butylcyclohexanones attempted to predict 7i-facial selectivity in that system. ... 

Table 5 Stereochemical outcome of nucleophilic additions to 5-substituted 2-adamantanones O...

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