A new phosphoramiditeligand was used in the iridium-catalyzed allylicsubstitution reaction. This permitted high regio- and enantioselectivities on a wide variety of substrates and nucleophiles. Because of the stereospecificity of the reaction obtained by using branched substrates, a kinetic resolution reaction was attempted. The origin of the impressive efficiency of this ligand in terms of kinetics
Bis(perfluoroalkyl) Phosphino-Oxazoline: A Modular, Stable, Strongly π-Accepting Ligand for Asymmetric Catalysis
作者:Zongjian Hu、Yuguang Li、Kai Liu、Qilong Shen
DOI:10.1021/jo3011717
日期:2012.9.21
A new class of stable, strongly π-accepting and modular bis(perfluoroalkyl)-phosphine-oxazoline ligands (FOX) as CO mimics was prepared. It was demonstrated that these ligands, when coordinated to palladium catalysts, promote the asymmetric alkylation of monosubstituted allyl substrates with excellent regio- and enantioselectivity. Solid and solution structure analysis of the FOX-ligated Pd-allyl intermediate
Very Efficient Phosphoramidite Ligand for Asymmetric Iridium-Catalyzed Allylic Alkylation
作者:Alexandre Alexakis、Damien Polet
DOI:10.1021/ol048607y
日期:2004.9.1
[reaction: see text] Linear or branched allylic carbonates or acetates undergo enantioselective iridium-catalyzedallylic substitution with sodium malonate. The reaction is wide in scope and affords the branched product in high yield and with high regio- (up to >99:1) and enantioselectivity (up to 98%). Ten aromatic or aliphatic substrates were successfully tested.
Enantioselective Ir-Catalyzed Allylic Alkylation of Racemic Allylic Alcohols with Malonates
作者:Chun-Yan Meng、Xiao Liang、Kun Wei、Yu-Rong Yang
DOI:10.1021/acs.orglett.8b04143
日期:2019.2.1
Ir-catalyzed enantioselective allylic alkylation of branched racemic allylicalcohols with malonates is described. Enabled by Carreira’s chiral Ir/(P, olefin) complex, the method described allows allylic substitution with various aromatic alcohols and malonates with excellent enantioselectivity. The malonates could be used directly as efficient nucleophiles without the need of preactivation.
An Ir-catalyzed asymmetric allylic alkylation using chiral diaminophosphine oxide is described. Asymmetric allylic alkylation of terminal allylic carbonates proceeded using 5 mol % of Ir catalyst, 5 mol % of DIAPHOX 1i, 10 mol % of NaPF6, 10 mol % of LiOAc, and N,O-bis(trimethylsilyl)acetamide (BSA), affording the corresponding branched products in excellent yield and in up to 95% ee. The developed