Hammett studies of enantiocontrol by PHOX ligands in Pd-catalyzed allylic substitution reactions

被引:39
作者
Constantine, RN [1 ]
Kim, N [1 ]
Bunt, RC [1 ]
机构
[1] Middlebury Coll, Dept Chem & Biochem, Middlebury, VT 05753 USA
关键词
D O I
10.1021/ol034610q
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
Electronically modified PHOX ligands 3a-e were synthesized to probe the mechanism of the enantioselective palladium-catalyzed allylic alkylation and amination reactions. Alkylation with dimethyl sodiomalonate produced only a small variation in the ee (89.3% to 93.4%), but amination with benzylamine gave a much wider variation in the ee (16.4% to 66.6%). Hammett analysis suggests that the substituents interact more significantly with phosphorus and supports a combined electronic and steric basis for enantioselection.
引用
收藏
页码:2279 / 2282
页数:4
相关论文
共 35 条
[1]  
Adams E, 1999, J ORG CHEM, V64, P8256
[2]   Synthesis, and solution and solid-state structures of (eta(3)-allyl){(4S)-4-benzyl-2-[2'-(diphenylphosphino)phenyl]-4,5-dihydrooxazole-P,N}palladium(II) hexafluorophosphates. Comparison with dichloro{(4S)-2-[2'-(diphenylphosphino)phenyl]-4,5-dihydro-4-phenyloxazole-P,N}zinc(II) [J].
Baltzer, N ;
Macko, L ;
Schaffner, S ;
Zehnder, M .
HELVETICA CHIMICA ACTA, 1996, 79 (03) :803-812
[3]   First-principles investigation of enantioselective catalysis: Asymmetric allylic amination with Pd complexes bearing P,N-ligands [J].
Blochl, PE ;
Togni, A .
ORGANOMETALLICS, 1996, 15 (20) :4125-4132
[4]   MECHANISTIC AND SYNTHETIC STUDIES IN CATALYTIC ALLYLIC ALKYLATION WITH PALLADIUM COMPLEXES OF 1-(2-DIPHENYLPHOSPHINO-1-NAPHTHYL)ISOQUINOLINE [J].
BROWN, JM ;
HULMES, DI ;
GUIRY, PJ .
TETRAHEDRON, 1994, 50 (15) :4493-4506
[5]  
Casey M, 2003, SYNLETT, P102
[6]   Remote electronic control of the ligand in the enantioselective palladium-catalyzed allylic alkylation with chiral oxazolinylpyridines [J].
Chelucci, G ;
Deriu, SP ;
Saba, A ;
Valenti, R .
TETRAHEDRON-ASYMMETRY, 1999, 10 (08) :1457-1464
[7]   Substituent effects on ligands on asymmetric induction in a prototypical palladium-catalyzed allylation reaction: Making both enantiomers of a product in high optical purity using the same source of chirality [J].
Clyne, DS ;
Mermet-Bouvier, YC ;
Nomura, N ;
RajanBabu, TV .
JOURNAL OF ORGANIC CHEMISTRY, 1999, 64 (20) :7601-7611
[8]   THE CHEMISTRY OF 2-OXAZOLINES (1985-PRESENT) [J].
GANT, TG ;
MEYERS, AI .
TETRAHEDRON, 1994, 50 (08) :2297-2360
[9]   A SURVEY OF HAMMETT SUBSTITUENT CONSTANTS AND RESONANCE AND FIELD PARAMETERS [J].
HANSCH, C ;
LEO, A ;
TAFT, RW .
CHEMICAL REVIEWS, 1991, 91 (02) :165-195
[10]   ASYMMETRIC-SYNTHESIS CATALYZED BY CHIRAL FERROCENYLPHOSPHINE TRANSITION-METAL COMPLEXES .8. PALLADIUM-CATALYZED ASYMMETRIC ALLYLIC AMINATION [J].
HAYASHI, T ;
YAMAMOTO, A ;
ITO, Y ;
NISHIOKA, E ;
MIURA, H ;
YANAGI, K .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1989, 111 (16) :6301-6311