The Conformation of a Diastereoisomeric Pair of 2,2-Dimethyl-4-phenyl-3-pentanols

Abstract

Abstract The conformations of a diastereoisomeric pair of 2,2-dimethyl-4-phenyl-3-pentanols were studied by means of 1H-NMR, 13C-NMR, IR, GC, and MS analyses. All of the results point to an unambiguous conclusion that these molecules are present dominantly in conformers where the t-butyl and the phenyl group lie close to each other. The generality of the phenomenon (favored gauche interaction) as well as the nature of the interactions involved were discussed in light of the conformational problems of the structurally related molecules. The presence of an attractive interaction (CH/π interaction) is suggested between an alkyl and a phenyl group, the possible importance of which in some dynamic phenomena (e.g., selectivities in certain reactions) has then been discussed on this basis.