Substituent Effects on Through-Bond Orbital Interaction-Induced Heterolysis of Some Perhydronaphthalenediol Monosulfonate Esters
作者:Romano V. A. Orru、Joannes B. P. A. Wijnberg、Aede de Groot
DOI:10.1021/jo00118a045
日期:1995.6
Substituent effects on the heterolysis of the perhydronaphthalene-1,4-diol monosulfonate esters 1, 7, and 8 induced by through-bond interactions (TBI) were studied. Evidence is found that, next to TBI, sigma-participation is the most important stereoelectronic effect which determines the reactivity of these compounds under strongly basic conditions in refluxing benzene. Substituents at carbon atoms adjacent to the carbon atom bearing the sulfonate ester group increase the contribution of a-participation which is expressed in a higher reactivity of these compounds. The product composition is primarily dependent on the degree of substitution at C(4). Homofragmentation and elimination are found when C(4) is unsubstituted as the reaction of mesylate 1 shows. Due to the repulsive 1,3-peri effect between the equatorial Me groups at C(4) and C(6) in the reaction of 7 and a combination of this 1,3-peri effect and the 4,4-dimethyl effect in that of 8, the ideal W arrangement is distorted. Consequently, no homofragmentation is observed with these compounds, and other reaction pathways (elimination, 1,3-H and 1,2-Me shifts) are now favored.