Antihydrophobic effect

Alkylations of phenoxide ions in water have recently been carefully studied by Breslow et al.57 Alkylation can occur both at the phenoxide oxygen and on ortho and para positions of the ring when the phenoxide has at least one alkyl substituent (Eq. 5.4). Carbon alkylation occurs in water, but not in nonpolar organic solvents. This is attributed to the antihydrophobic effect of the organic solvents. 

Breslow R. Hydrophobic and Antihydrophobic Effects on Organic Reactions in Aqueous Solution. In Cramer CJ, Truhlar DG (eds.), Structure and Reactivity in Aqueous Solution Characterization of Chemical and Biological Systems (ACS Symposium Series). American Chemical Society, Washington DC, 1994, pp. 291-302. 

Breslow R, Connors R, Zhu Z. Mechanistic studies using antihydrophobic effects. Pure and Appl Chem 1996 68 1527-1533. 

Breslow R, Zhu Z. Quantitative antihydrophobic effects as probes for transition state structures. J Am Chem Soc 1995 117 9923-9924. 

Breslow R. Hydrophobic and antihydrophobic effects on organic reactions in aqueous solution. Struct React Aq Sol 1994 568 291-302. 

As part of our exploration of these effects, we also looked at solvents that are waterlike and the effects of additives in them. We saw that these additives did not show antihydrophobic effects in ethylene glycol, in acetonitrile, or in dimethylsulfoxide. Apparently the interface of a hydrocarbon surface with these solvents is sufficiently stable that no bridging by an additive is required to lower the energy. 

Quantitative antihydrophobic effects in water and the geometries of transition states... 

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