Neophyl compounds

Kinetic analysis of this system enables the data of Table 20 to be derived. The ratios k 3/k2 give a measure of the relative catalytic effectiveness of the cations since k2 is independent of the electrophile. The resulting order, Li+ > K+ > n-Bu4N+, is similar to that reported for the electrophile-assisted ionizations of p-methoxy-neophyl tosylate and the p-nitrobenzoate of spiro- [4,5 ] -deca-6,9-dien-8-ol in acetone (Winstein et al., 1964). The absence of these effects with the chloro compound is in accord with the observations that aromatic chloro derivatives are not usually subject to electrophilic catalysis of leaving group departure (Bemasconi, 1973). 

Neophyl(tri- -butylphosphine)copper decomposes at temperatures between 30° and 120°C mainly, if not totally, by a free-radical mechanism. The usual products resulting from rearrangement of the neophyl radical were isolated [Eq. (37)], and no evidence was obtained to indicate the formation of an intermediate phenyl-substituted tert-hu. y -copper compound, C6H5CH2(CH3)aCCu. 

The neophyl derivative of yttrium is formed by the same mechanism. The fact that 2 moles of tert-butyl benzene are evolved per yttrium in this reaction indicates the possible formation of a compound containing an yttrium-carbon triple bond (Guzman et al., 1979 Dolgoplosk et al., 1980) ... 

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