10468-24-3Relevant academic research and scientific papers
Asymmetrie copper-catalyzed propargylic substitution reaction of propargylic acetates with enamines
Fang, Ping,Hou, Xue-Long
supporting information; experimental part, p. 4612 - 4615 (2009/12/09)
Enamines served as carbon-nucleophiles for the first time In the Cu-catalyzed asymmetric propargylic substitution reaction of propargylic acetates, providing corresponding chiral β-ethynyl-substituted ketones In high yields and In good to high enantioselectivity.
Base-promoted reactions of dichlorocarbene adducts of cyclic enamines: A new route to annulated pyrroles
Bissember, Alex C.,Phillis, Andrew T.,Banwell, Martin G.,Willis, Anthony C.
, p. 5421 - 5424 (2008/09/17)
Treatment of the gem-dihalogenocyclopropanes 1-5 with potassium tert-butoxide or LDA results in the formation of the corresponding and annulated pyrroles 13-17, respectively.
178. Stereoselectivity of the Radical Reductive Alkylation of Enamines: Importance of the Allylic 1,3-Strain Model
Schubert, Serge,Renaud, Philippe,Carrupt, Pierre-Alain,Schenk, Kurt
, p. 2473 - 2489 (2007/10/02)
Radical addition to enamines using Bu3SnH as reducing agent are reported (Schemes 2 and 4).The diastereoselectivity of these reactions was examined in different systems (Tables 1 and 2).Enamines derived from cyclic ketones such as cyclohexanone were alkyl
THE ?-BARRIER TO ROTATION IN STERICALLY UNHINDERED ENAMINES: CONFORMATIONAL STUDIES BY DYNAMIC NMR, XXXVIII
Lunazzi, Lodovico,Casarini, Daniele,Anderson, J.Edgar
, p. 217 - 221 (2007/10/02)
The ?-barriers to rotation about the enamine (N-Csp2) bond in four pyrrolidinocyclo-n-alkenes (n = 5, 6, 7, 8) have been determined, and are discussed in terms of the steric interactions between the pyrrolidine and cycloalkene rings in the ground state.Distinct barriers were determined for two different conformations of the cyclooctene ring.Barriers were determined in two acyclic N,N-(dialkylamino)cycloalkenes for reference comparison.
HIGHLY ENANTIOSELECTIVE ISOMERIZATION OF PROCHIRAL ALLYLAMINES CATALYZED BY CHIRAL DIPHOSPHINE RHODIUM(I) COMPLEXES. PREPARATION OF OPTICALLY ACTIVE ENAMINES
Tani, Kazuhide,Yamagata, Tsuneaki,Akutagawa, Susumu,Kumobayashi, Hidenori,Taketomi, Takanao,et al.
, p. 5208 - 5217 (2007/10/02)
Rh(I) complexes of types ClO4 and n>ClO4 (diphosphine = cis-chelating tertiary diphosphine; diene = 1,5-cyclooctadiene or norbornadiene; S = solvent) were found to be effective catalists for allylic hydrogen migration of tertiary and secondary allylamines to give the corresponding (E)-enamines and imines, respectively.Studies on diphosphine ligands with respect to the catalytic activity and product selectivity led to the discovery of a fully aryl-substituted diphosphine, BINAP , which produces very active Rh(I) complex catalysts.With ClO4 (COD = 1,5-cyclooctadiene) or n>ClO4 as catalyst, (Z)-(diethylnerylamine, 1) or (E)-N,N-diethyl-3,7-dimethyl-2,6-octadienylamine (diethylgeranylamine, 2) was isomerized into the racemic (E)-enamine (E)-N,N-diethyl-3,7dimethyl-1,6-octadienylamine (citronellenamine, 3) with a chemical selectivity of over 95percent, the 6-double bond being retained intact.A variety of substituted allylamines serves as the substrate, e.g., (E)-N,N-dimethyl-2-butenylamine, N,N-dimethyl-2-methyl-2-propenylamine, N,N-dimethyl-3-methyl-2-butenylamine, N,N-dimethyl-3-phenyl-2-butenylamine.Asymmetric isomerization of prochiral allylamines producing optically active enamines or imines can be effected with cationic Rh(I) complexes of various chiral diphosphine ligands such as (2R,3R)-DIOP and others.The ligand that gives the highest optical yield was (+)- or (-)-BINAP.Virtually perfect enantioselectivity (95-99percent ee) was achieved with + for the isomerization of 1 or 2 into the optically active (E)-enamine (3).A clear stereochemical correlation was established between the olefin geometry (E or Z) of substrates, the configuration of the chiral diphosphines (R or S), and the chiral carbon configuration of the product enamines (R or S).The present catalytic system thus provides a convenient and practical access to optically active aldehydes.For example, optically pure natural citronellal can be produced either from nerylamine with the Rh(I)-(+)-BINAP catalyst or from geranylamine with the Rh(I)-(-)-BINAP complex catalyst.
