Fig. 4: Comparison of alkylation methods.
From: Carbocationoids, a concept for controlling highly reactive cationic species
a Attempts at the alkylation of alcohol 6 using benzyl iodides 43a or 43b. b Attempts at the alkylation of silyl enol ether 15 using benzyl iodides 43a or 43b. c Selective formation of asymmetric ether 8ad through a stepwise procedure of carbocationoid formation followed by alkylation. d Unselective ether formation reactions promoted by an acidic catalyst system. * indicates a ratio or a yield calculated by 1H NMR spectroscopy. †indicates an isolated yield. e The N-alkylation of sterically hindered secondary amine 44 using carbocationoid 3b. f Attempts at the acid-catalyzed N-alkylation of 44 using trichloroacetimidate 46 and trifluoromethanesulfonic acid.
