131516-15-9Relevant academic research and scientific papers
Palladium-catalyzed asymmetric intermolecular arylation of cyclic or acyclic alkenes using phosphinite-oxazoline ligands derived from D-glucosamine
Yonehara, Koji,Mori, Kenji,Hashizume, Tomohiro,Chung, Kang-Go,Ohe, Kouichi,Uemura, Sakae
, p. 40 - 49 (2000)
Chiral phosphinite-oxazolines, 2-alkyl- or 2-aryl-4,5-(4,6-O-benzylidene-3-O-(diphenylphosphino)-1,2-di-deoxy-a-D- glucopyra-nosyl)-[2,1-d]-2-oxazolines 1a-f derived from D-glucosamine hydrochloride, are revealed to work as effective P,N-bidentate ligands in the palladium-catalyzed enantioselective arylation of 2,3-dihydrofuran to give 2-aryl-2,5-dihydrofuran selectively in high yield with up to 96% ee. The first asymmetric phenylation reaction of trans and cis-crotyl alcohols as acyclic alkenes with iodobenzene is also carried out to afford 3-phenylbutanal in moderate chemical yield with up to 17% ee. The complex [PdCl2(1b)] is newly prepared and its structure is characterized by X-ray crystallography. Structures of the new complex [(p-MeO2CC6H4)PdI(1a)] (8) and its cationic complex [(p-MeO2CC6H4)Pd(1a)]+OTf - (9) are also elucidated on the basis of 1H-, 13C-, and 31P-NMR spectra, p-MeO2CC6H4 moiety on the palladium being located trans to the nitrogen of 1a. This configuration might be responsible for an enantiofacial discrimination of 2,3-dihydrofuran to produce (R) isomer predominantly. The stoichiometric reaction of [PhPd(1f)]+OTf- (11) with 2,3-dihydrofuran has provided the mechanistic aspect for the arylation using P,N-ligands, in which the base-promoted deprotonation at β-position leading to an alkene(2-aryl-2,5-dihydrofuran)-palladium(0) complex has been shown to be an important step for the selective formation of the product.
SPIRO-1,1'-BIINDANE-7,7-BISPHOSPHINE OXIDES AS HIGHLY ACTIVE SUPPORTING LIGANDS FOR PALLADIUM-CATALYZED ASYMMETRIC HECK REACTION
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Page/Page column 35, (2015/01/06)
The present invention relates to catalyst complexes comprising palladium (Pd) and at least one spiro-1,1 '-biindane-7,7'- bisphosphine oxide ligand as disclosed herein, and their use. The present invention is further directed to the asymmetric Pd-catalyzed covalent carbon-carbon single bond formation from aryl, heteroaryl and alkenyl triflates and halides and olefins utilising the said catalyst complexes.
Asymmetric intermolecular heck reaction of aryl halides
Wu, Chunlin,Zhou, Jianrong
supporting information, p. 650 - 652 (2014/02/14)
The asymmetric intermolecular Heck reaction has been limited to aryl and vinyl triflates. Herein, we extend the reaction to aryl and vinyl bromides. Various cyclic olefins coupled with high enantioselectivity. Only bisphosphine oxides on a spiro backbone formed highly stereoselective Pd catalysts. The use of alcoholic solvents and alkylammonium salts were essential to promote halide dissociation from neutral arylpalladium complexes.
Highly active catalysts of bisphosphine oxides for asymmetric Heck reaction
Hu, Jian,Lu, Yunpeng,Li, Yongxin,Zhou, Jianrong
, p. 9425 - 9427 (2013/10/01)
Bisphosphine oxides formed highly active asymmetric Heck catalysts, which were applied in asymmetric synthesis of pharmacologically active azacycles. Olefin insertion proceeded via cis pathways, different from P,N-ligands.
Palladium-catalyzed asymmetric Heck arylation of 2,3-dihydrofuran-effect of prolinate salts
Morel, Adam,Silarska, Ewelina,Trzeciak, Anna M.,Pernak, Juliusz
, p. 1215 - 1222 (2013/02/23)
Chiral ionic liquids (CILs) containing l-prolinate and l-lactate anions and non-chiral quaternary ammonium cations were employed in the palladium catalyzed enantioselective Heck arylation of 2,3-dihydrofuran with aryl iodides (iodobenzene, 4-iodotoluene, 2-iodoanisole, 4-iodoanisole, 4-iodoacetophenone). In all the reactions 2-aryl-2,3-dihydrofuran (3) was obtained as the main product with the yield up to 52% at the total conversion reaching 83%. Product 3, 2-phenyl-2,3-dihydrofuran, was obtained with excellent enantioselectivity (>99% ee) in a 6 h reaction with tetrabutylammonium l-prolinate. In the proposed homogeneous reaction Pd(0) nanoparticles are considered as a resting state of the catalyst and a source of soluble palladium species catalyzing the Heck reaction. The yield and stereoselectivity of the Heck reaction are strongly influenced by the kind of non-chiral cations present in CILs. The Royal Society of Chemistry 2013.
A dramatic switch of enantioselectivity in asymmetric heck reaction by benzylic substituents of ligands
Wu, Wen-Qiong,Peng, Qian,Dong, Da-Xuan,Hou, Xue-Long,Wu, Yun-Dong
experimental part, p. 9717 - 9725 (2009/02/04)
A series of benzylic substituted P,N-ligands 1 and 2 have been synthesized. The Pd-complexes of these ligands show high catalytic activity and enantioselectivity in catalyzing the asymmetric Heck reaction. A dramatic switch in enantioselectivity is realized using ligands with and without substituents at the benzylic position of the ligand. Ligands 1 with H as the substituents offer products in (R)-configuration while ligands 2 with the methyl as substituents result in (S)-configuration products. In most cases high enantioselectivities are achieved. Density functional theory calculations on the reaction mechanism as well as X-ray analysis of 1a-PdCl2 and 2a-PdCl2 complexes provide a rational explanation for the above observations.
Microwave-assisted asymmetric intermolecular heck reaction using phosphine-thiazole ligands
Kaukoranta, Paeivi,Kaellstroem, Klas,Andersson, Pher G.
, p. 2595 - 2602 (2008/09/19)
A series of new phosphine-thiazole compounds has been synthesized and used as efficient ligands in the palladium-catalyzed asymmetric intermolecular Heck coupling of 2,3-dihydrofuran with aryl triflates and cyclohexenyl triflate. Microwave heating was used to accelerate the reactions and gave complete conversions in as little as one hour. Products were obtained with good to excellent enantioselectivities.
The regioselectivity of the asymmetric intermolecular Heck reaction with planar chiral diphosphine-oxazoline ferrocenyl ligands
Tu, Tao,Deng, Wei-Ping,Hou, Xue-Long,Dai, Li-Xin,Dong, Xi-Cheng
, p. 3073 - 3081 (2007/10/03)
A series of novel planar chiral diphosphine-oxazoline ferrocenyl ligands were synthesized and used efficiently in the palladium-catalyzed asymmetric intermolecular Heck reaction of 2,3-dihydrofuran with aryl triflate and cyclohexenyl triflate. The tuning of the regioselectivity was realized by means of different palladium precursors and by changing the electronic factor of the ligands. A plausible rationale based on the existed mechanism is provided.
Microwave-assisted enantioselective Heck reactions: Expediting high reaction speed and preparative convenience
Nilsson, Peter,Gold, Henrik,Larhed, Mats,Hallberg, Anders
, p. 1611 - 1614 (2007/10/03)
Palladium-catalyzed asymmetric Heck reactions have been performed using high temperature conditions with the aid of controlled microwave dielectric heating. Significant enantioselectivities of up to 92% ee were obtained under non-inert conditions utilizin
Palladium-catalyzed asymmetric arylation of 2,3-dihydrofuran: 1,8-Bis(dimethylamino)naphthalene as an efficient base
Ozawa, Fumiyuki,Kubo, Akihiko,Hayashi, Tamio
, p. 1485 - 1488 (2007/10/02)
Reaction of 2,3-dihydrofuran with aryl triflate (1) in the presence of a base and a palladium catalyst, generated in situ from Pd(OAc)2 and (R)-BINAP, gave (R)-2-aryl-2,3-dihydrofuran (2) and a small amount of (S)-2-aryl-2,5-dihydrofuran (3). T
