66399-53-9Relevant academic research and scientific papers
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.
Catalytic asymmetric hydroboration/amination and alkylamination with rhodium complexes of 1,1′-(2-diarylphosphino-1-naphthyl)isoquinoline
Fernandez, Elena,Maeda, Kenji,Hooper, Mark W.,Brown, John M.
, p. 1840 - 1846 (2007/10/03)
Catecholboronate esters formed by asymmetric hydroboration of arylalkenes are not directly converted to amines by reaction with hydroxylamine-O-sulfonic acid. Prior conversion to a trialkylborane by reaction with ZnEt2 or MeMgCl permits a subsequent amination reaction to occur with essentially complete retention of configuration, leading to a range of primary α-arylalkylamines in up to 97% enantiomeric excess (ee). Secondary, but not tertiary amines may be formed by a related pathway when in situ generated alkylchloramines are employed as the aminating agent. The catalytic asymmetric hydroboration, β-alkylation and amination steps may be combined in a single stage. Overall, this provides a practical procedure for the synthesis of enantiomerically enriched arylamines, exemplified inter alia by the synthesis of (S)-1,2,3,4-tetrahydro-1-naphthylamine in 95-97% ee and of (R)-N-(cyclohexyl)-1′-(4-methoxyphenyl)ethylamine in 93 % ee.
