Solvation-dependent diastereofacial selectivity: addition of lithioacetonitrile to 2-phenyl propanal

Solvent effects on stereoselectivity: more than just an environment

“…19). 37 In this case, we observed an opposite temperature behaviour in the diastereomeric ratio for reactions in n-hexane vs. n-hexane/n-Bu 3 N and methylcyclohexane. We have already observed opposite concavities for the Eyring plots of cyclic vs. linear hydrocarbons in the addition of n-BuLi to 2-phenylpropanal.…”

Chemical reactivity and solution structure: on the way to a paradigm shift?

“…Basing on extensive experimental studies, [140][141][142][143][144][145][146][147][148][149][150][151][152][153] which have been reviewed, 140 Cainelli et al analysed the inuence of variety of solvents (aliphatic and aromatic hydrocarbons, halohydrocarbons, ethers) and their mixtures on temperature dependences of the ratio of stereoisomers formed in many types of stereoselective reactions (nucleophilic additions, cycloadditions, photochemical and enzymatic reactions). Eyring plots of enantiomeric (or diastereomeric) ratios were found to be nonlinear in many cases, two or more linear segments being separated by "inversion temperature (T inv )" (Fig.…”

Reactions of Aldehydes and Ketones and their Derivatives

“…255 The diastereofacial selectivity of the addition of lithioacetonitrile to 2-phenylpropanol has been studied over a wide range of temperatures, solvents, and bases. 256 Eyring plots [ln(dr) vs 1/T ], activation parameters, and inversion temperatures have de been characterized. In some cases, the differential entropy of activation, S = , plays an exclusive role in determining anti -selectivity.…”