Systematic Study of Halide-Induced Ring Opening of 2-Substituted Aziridinium Salts and Theoretical Rationalization of the Reaction Pathways

摘要: The ring-opening reactions of 2-alkyl-substituted 1,1-bis(arylmethyl)- and 1-methyl-1-(1-phenylethyl)aziridinium salts with fluoride, chloride, bromide iodide in acetonitrile have been evaluated for the first time a systematic way. fluoride afforded regioisomeric mixtures primary secondary fluorides, whereas β-chloro, β-bromo β-iodo amines were obtained as sole reaction products from corresponding halides by regiospecific ring opening at substituted position. Both experimental computational results revealed that outcomes cases dictated product stability through thermodynamic control involving rearrangement initially formed to more stable halides. same aziridinium however, was shown be mediated steric interactions (kinetic control), β-fluoro being main products. Only 2-acylaziridinium ions outcome under full substrate control, affording β-fluoro, exclusive attack activated α-carbonyl carbon atom.