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Phenyldimethylcarbinol and its o-, m-and ^-monoalkvl (methyl, ethyl, isopropyl and Z-butyl) derivatives were synthesized. With one exception, these carbinols were converted readily to the corresponding tertiary chlorides by treatment with hydrogen chloride. The failure of o-Z-butylphenyldimethylcarbinol to yield the expected tertiary chloride is attributed to the large strains to be expected in this molecule, a homomorph of the unknown y-di-Z-butylbenzene. The rates of hydrolysis of the various tertiary chlorides in 90% aqueous acetone were measured at several temperatures. The small increase in rate (25°) observed in the meta alkyl derivatives ( , 1.00; m-Me, 2.00; w-Et, 1.94; m-i-Pr, 1.87; m-Z-Bu, 1.85) is attributed primarily to the inductive effect of the substituent. The minor decrease in effect with increased branching is attributed to a small hyperconjugative contribution transmitted to the ortho position of the aromatic ring and relayed to the reaction center by induction. The much larger effect of the para alkyl groups (p-Me, 26.0; p-Et, 22.0; p-i-Pr, 18.8; p-t-Bu., 14.4) is attributed to hyperconjugation stabilization of the electron deficient center by the alkyl group. From the observation that both in the meta and para positions methyl and Z-butyl groups have similar effects, it is concluded that carbon-to-carbon hyperconjugation must be nearly as important as carbon-to-hydrogen hyperconjugation. A methyl group in the ortho position (o-Me, 3.63) is far less important than a methyl group in the ^-position (p-Me, 26.0). This is attributed to steric hindrance of resonance in the transition state. With increasing bulk of the ortho substituent, the effect increases (c-Et, 2.07; o-i'-Pr, 0.847). The rate data obey the empirical relationship, log p¡ = c log (pi!mi), previously developed for the substitution reactions of toluene.

The base-catalyzed reaction of vinylphosphonium salts with compounds containing replaceable hydrogen introduces a 2-substituted ethylphosphonium group. This reaction is called phosphonioethylation. Addition to tributylvinylphosphonium bromide of compounds containing -CH, -NH, -PH, -OH, and -SH has been carried out. Other vinylphosphonium salts react similarly. Diels-Alder addition of cyclopentadiene and brom ¡nation also have been observed. The adduct with isobutyrophenone undergoes intramolecular cyclization in the presence of base to give a cyclobutenylphosphonium salt. Michael addition to allylphosphonium salts has been investigated.

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