Factors influencing the reverse-Cope approach to 1,2,5-oxadiazinanes from allylamines and nitrones: Optimization of a new vicinal diamine synthesis
摘要:
Nitrones generated from formaldehyde and N-alkyl-hydroxylamines are particularly suitable reactants in tandem reverse-Cope-Meisenheimer reactions leading to oxadiazinanes and thence N-hydroxydiamines and vicinal diamines, front allylamines. (C) 1997 Elsevier Science Ltd.
Asymmetricallylicsubstitutionreactions between 1,3-diphenyl-2-propenyl acetate and various hetero nucleophiles were efficiently carried out using the catalysts derived from the monodentatephosphine ligands, (1R, 2S, 5R, 6S)-2,6-dimethyl-9-phenyl-9-phosphabicyclo[3.3.1] nonane and its enantiomer ((−)- and (+)-9-PBNs), and palladium (0).
A Widely Applicable Chiral Auxiliary, <i>cis</i>-2-Amino-3,3-dimethyl-1-indanol: Conversion to a Novel Phosphorus-Containing Oxazoline and Its Application as a Highly Efficient Ligand for the Palladium-Catalyzed Enantioselective Allylic Amination Reaction
作者:Atsushi Sudo、Kazuhiko Saigo
DOI:10.1021/jo970359e
日期:1997.8.1
A chiral amino alcohol, cis-2-amino-3,3-dimethyl-1-indanol (2), was converted into the corresponding enantiomerically pure phosphorus-containing oxazoline 4. Oxazoline 4 was found to be an efficient ligand for palladium-catalyzed enantioselective allylic amination reactions: In the amination reaction of (E)-1,3-diphenyl-2-propen-1-yl acetate (7a), 4 was found to be more efficient than the similar ligands 1a-c, derived from valinol, tert-leucinol, etc. Other 1,3-bis(p-substituted aryl)-2-propen-1-yl acetates were also converted to the corresponding amines in a similar manner and with excellent enantioselectivity. In the amination reaction of 1-alkyl-3,3-diphenyl-2-propen-1-yl acetates 11, the correponding amines 12 were obtained with excellent enantioselectivity when acetic acid was added to the reaction system.