Gas-Phase Reactions of Charged Electrophiles with Styrene and Phenylacetylene

Article abstract of DOI:10.1021/ja00198a006

The reactions of styrene and phenylacetylene toward charged electrophiles have been studied in the gas phase by a radiolytic technique, supported by chemical ionization mass spectrometry.The two substrates undergo a methylation reaction by Me2F(1+) both at the ring and at the side chain, at variance with the side-chain electrophilic attack prevailing in condensed phase.The nitrating (MeONO2)H(1+) ion selectively nitrates the orto position of styrene, an unprecedented ring nitration on this substrate.The formation of neutral isomeric products is determined by the efficiency of deprotonation of their ionic precursors and is sensitive interalia to the presence of oxygen nucleophiles.The overall reactivity pattern is rationalized in terms of preferential electrostatic interactions between the reactants in a preliminary collision complex, whereby an incoming ROH molecule can simulate a "solvating" environment, shifting the reactivity in the direction observed in solution.