29412-58-6Relevant articles and documents
Selective Hydrogen Transfer in N-(Diphenylmethyl)-1-phenylethan-1-imine
Li, J.,Shi, Y. B.,Xing, J. D.
, p. 589 - 597 (2021/06/02)
Abstract: Proton transfer processes mediate many organic reactions. How to realizestereochemical control of this process has always been a challenging topic inthe field of asymmetric catalysis. In this study, N-(diphenyl-methyl)-1-phenylethan-1-imine (Schiff base derivedfrom 2,2-diphenylethan-1-amine and acetophenone) was used as substrate, anddifferent near neutral solvents and various chiral metal complex catalysts wereused to carry out photoinduced C=N double bond transfer in the substrate underirradiation with a mercury ultraviolet lamp. The double bond transfer in thesubstrate molecule was highly selective. Solvents containing strongelectronegative atoms like oxygen and chlorine, such as alcohols, aldehydes, andcarbon tetrachloride, were more effective than other solvents under high lightintensity. The 1,3-proton transfer process involves photo-excitation of theSchiff base and coordination of the latter to the central metal atom of thechiral catalyst, so that the substrate molecule is placed in a stable chiralenvironment to form a transition state. The strongly electro-negative atom ofthe near-neutral solvent attracts the active α-hydrogen from the excited Schiffbase molecule to form a negatively charged delocalized π-bond structure. Thesubsequent proton addition yields more stable molec-ular structure to completethe selective proton transfer process. Among the examined chiral catalysts,divalent tin porphyrin was the most effective, and the product yield andenantiomeric excess were 98% and 91.49%, respectively. The describedphotoinduced C=N double bond transfer in N-(diphenylmethyl)-1-phenyl-ethan-1-imine is characterized by mildconditions (room temperature), high stereoselectivity, and simpleoperation.
Enantioselective reduction of: N -alkyl ketimines with frustrated Lewis pair catalysis using chiral borenium ions
Mercea, Dan M.,Howlett, Michael G.,Piascik, Adam D.,Scott, Daniel J.,Steven, Alan,Ashley, Andrew E.,Fuchter, Matthew J.
supporting information, p. 7077 - 7080 (2019/06/20)
Enantioselective reduction of ketimines was demonstrated using chiral N-heterocyclic carbene (NHC)-stabilised borenium ions in frustrated Lewis pair catalysis. High levels of enantioselectivity were achieved for substrates featuring secondary N-alkyl substituents. Comparative reactivity and mechanistic studies identify key determinants required to achieve useful enantioselectivity and represent a step forward in the further development of enantioselective FLP methodologies.
Oxidative conversion of imines into 2-azadienes
Capra, Julien,Le Gall, Thierry
scheme or table, p. 441 - 444 (2010/04/24)
Several 2-azadienes were prepared by treatment of imines derived from diphenylmethanamine and ketones with sodium hydride in DMF under an air atmosphere. Georg Thieme Verlag Stuttgart New York.