Disproportionative Condensations. II. The N-Alkylation of Anilines with Primary Alcohols

Base‐Mediated Transition‐Metal‐Free Dehydrative C−C and C−N Bond‐Forming Reactions from Alcohols

“…Thirty years after, Pratt and Frazza reported that a 92 % yield of N ‐benzylaniline was obtained by heating in refluxing xylene aniline (0.125 mol) and an excess of benzyl alcohol (0.185 mol) in the presence of potassium benzylated (0.06 mol) and catalytic U.O.P. nickel . Interestingly, in an experiment performed to determine the need for the metal catalyst, N ‐benzyl aniline could still be obtained in 94 % yield by performing the reaction without nickel under solvent‐free conditions at a higher temperature (189–227 °C).…”

“… Mechanism in the Meerwein‐Ponndorf‐Verley (MPV)‐reduction of benzylamines with electron‐releasing substituents on the alcohol 63 or on the amine 64 …”

“…Under these reaction conditions both amines and diamines were monobenzylated in very good yields (Scheme ). In some instances, the addition of a small amount of benzaldehyde increased the reaction rate since the aldehyde promotes the formation of the imine …”

“…ethanol in a sealed tube at 210-220°C for 16 hours (Scheme 19). [29] These reaction conditions were also successful to alkylate fluorene 24 at the 9-position with various linear aliphatic alcohols (9). Noteworthy, the alkylation reaction of octadecanol was carried out at atmospheric pressure by using an excess of fluorene (Scheme 19).…”

“…TM-free alkylation processes with alcohols have been known since at least 1892, [8] and in the 1950s even the mechanistic aspects of these transformations had already been hypothesized. [9] However, these early methods demanded harsh reaction conditions, such as high pressure (sealed tube), very high temperature (250-350°C) and a large excess of alcohol and base, with consequent limitations in the reaction scope.…”