64275-32-7Relevant academic research and scientific papers
Rapid Access to Highly Functionalized Alkyl Boronates by NiH-Catalyzed Remote Hydroarylation of Boron-Containing Alkenes
Zhang, Yao,Han, Bo,Zhu, Shaolin
, p. 13860 - 13864 (2019/08/08)
The direct and selective functionalization of relatively simple and readily accessible precursors to produce highly functionalized alkyl boronates is a synthetically useful process. Herein we report a NiH-catalyzed remote hydroarylation process that can, through a synergistic combination of chain walking and subsequent cross-coupling, introduce an aryl group at the adjacent carbon atom of alkyl boronates under mild conditions. By means of a preliminary experiment with moderate enantioselectivity, it was shown that an asymmetric version could also be realized.
Reactivity of mixed organozinc and mixed organocopper reagents: 14. Phosphine-nickel catalyzed aryl-allyl coupling of (n-butyl)(aryl)zincs. Ligand and substrate control on the group selectivity and regioselectivity
Kalkan, Melike,Erdik, Ender
, p. 28 - 36 (2016/06/09)
The group selectivity and regioselectivity in the allylation of mixed (n-butyl)(aryl)zinc reagents in THF depends on the nickel catalyst type and also on nature of the allylic substrate. Allylation of (n-butyl)(phenyl)zinc reagent with alkyl substituted primary allylic chlorides and acetates in the presence of NiCl2(dppf) catalysis affords the phenyl coupling product with γ-selectivity. However, allylation with aryl substituted primary allylic substrates results in both phenyl- and alkyl-coupling products with medium α-selectivity in the presence of NiCl2(dppf) catalysis whereas phenyl coupling product is formed with α-selectivity in the presence of NiCl2(Ph3P)2 catalysis. This new NiCl2(dppf) catalyzed protocol for γ-selective aryl allylation of (n-butyl)(aryl)zinc reagents with alkyl substituted primary allylic chlorides in THF at room temperature provides an atom economic alternative to allylation of (aryl)2Zn reagents. A mechanism for the dependence of group selectivity and regioselectivity of Ni catalyzed allylation of (n-butyl)(aryl)zinc reagents on the catalyst ligand and the substrate was proposed.
Rhodium-catalyzed asymmetric coupling reaction of allylic ethers with arylboronic acids
Kiuchi, Hiroyoshi,Takahashi, Dai,Funaki, Kenji,Sato, Tetsuo,Oi, Shuichi
supporting information, p. 4502 - 4505 (2012/10/29)
An asymmetric allylic substitution of simple allylic ethers with arylboronic acids in the presence of a rhodium(I)/(R)-DTBM-SEGPHOS catalyst has been developed. The reactions proceeded smoothly at room temperature to give the corresponding branch products with excellent regioselectivities and good to excellent enantioselectivities.
Short synthesis of chiral 4-substituted (S)-imidazolinium salts bearing sulfonates and their use in γ-selective reactions of allylic halides with grignard reagents
Latham, Christopher M.,Blake, Alexander J.,Lewis, William,Lawrence, Matthew,Woodward, Simon
supporting information; experimental part, p. 699 - 707 (2012/03/11)
A one-pot reaction of Boc-protected amino alcohols and 2-sulfobenzoic anhydride followed by the addition of a wide variety of primary amines has allowed rapid access to diverse libraries of amidosulfonates 1,2-C 6H4(SO3su
Ligand effects in chromium diphosphine catalysed olefin co-trimerisation and diene trimerisation
Bowen, Lucy E.,Charernsuk, Manutsavin,Hey, Thomas W.,McMullin, Claire L.,Orpen, A. Guy,Wass, Duncan F.
experimental part, p. 560 - 567 (2010/04/03)
A series of symmetric and unsymmetric N,N-bis(diarylphosphino)amine ('PNP') ligands (Ar2PN(R)PNAr′2: R = Me, Ar2 = o-anisyl, Ar′2 = Ph, 1, R = Me, Ar2 = o-tolyl, Ar′2 = Ph, 2, R = Me, Ar2 = Ph(o-ethyl), Ar′2 = Ph, 3, R = Me, Ar2 = Ar′2 = o-anisyl, 4, R = iPr, Ar2 = Ar′2 = Ph, 5) and symmetric N,N′-bis(diarylphosphino)dimethylhydrazine ('PNNP') ligands (Ar2PN(Me)N(Me)PAr2: Ar2 = o-tolyl, 6, Ar 2 = o-anisyl, 7) have been synthesised. Catalytic screening for ethene/styrene co-trimerisation and isoprene trimerisation was performed via the in situ complexation to [CrCl3(THF)3] followed by activation with methylaluminoxane (MAO). PNNP catalytic systems showed a significant increase in activity and selectivity over previously reported PNP systems in isoprene trimerisation. Comparing the symmetric and unsymmetric variants in ethene and styrene co-trimerisation resulted in a switch in selectivity, an unsymmetric catalytic (o-anisyl)2PN(Me)PPh 2 (1) ligand system affording unique incorporation of two styrenic monomers into the co-trimer product distribution differing from the familiar two ethene and one styrene ω-substituted alkenes. Complexes of the type [(diphosphine)Cr(CO)4] 8-11 were also synthesised, the single-crystal X-ray diffraction of which are reported. We propose the mechanisms of these catalytic transformations and an insight into the effect of the ligand series on the chromacyclic catalytic intermediates. The Royal Society of Chemistry.
Enantioselective iridium-catalyzed allylic arylation
Polet, Damien,Rathgeb, Xavier,Falciola, Caroline A.,Langlois, Jean-Baptiste,El Hajjaji, Samir,Alexakis, Alexandre
supporting information; experimental part, p. 1205 - 1216 (2009/09/06)
We describe herein the development of the first iridium-catalyzed allylic substitution using arylzinc nucleophiles. High enantioselectivities were obtained from the reactions, which used commercially available Grignard reagents as the starting materials. This methodology was also shown to be compatible with halogen/metal exchange reactions. Its synthetic potential is demonstrated by its application towards the formal synthesis of (+)-sertraline.
Synthesis of Farnesol Analogues through Cu(I)-Mediated Displacements of Allylic THP Ethers by Grignard Reagents
Mechelke, Mark F.,Wiemer, David F.
, p. 4821 - 4829 (2007/10/03)
The synthesis of a family of farnesol analogues, incorporating aromatic rings, has been achieved in high yields through the development of a regioselective coupling of allylic tetrahydropyranyl ethers with organometallic reagents. The allylic THP group is displaced readily by Grignard reagents in the presence of Cu(I) halides but is stable in the absence of added copper. Thus, an allylic THP group can fulfill its traditional role as a protecting group or serve as a leaving group depending on reaction conditions. An improved synthesis of (2E,6E)-10,11-dihydrofarnesol also has been accomplished using this methodology, and some preliminary studies on the reactivity and regioselectivity of THP ether displacements were conducted. The farnesol analogues reported herein may be useful probes of the importance of nonbonding interactions in enzymatic recognition of the farnesyl chain and allow development of more potent competitive inhibitors of enzymes such as farnesyl protein transferase.
REGIO- AND STEREO-CHEMISTRY IN ALLYLATION OF ARYL GRINARD REAGENTS CATALYZED BY PHOSPHINE-NICKEL AND -PALLADIUM COMPLEXES
Hayashi, Tamio,Konishi, Mitsuo,Yokota, Kan-Ichi,Kumada, Makoto
, p. 359 - 374 (2007/10/02)
Nickel and palladium complexes with the 1,1'-bis(diphenylphosphino)ferrocene ligand effectively catalyze regioselective cross-coupling of allylic ethers such as 1- or 3-methyl-2-propenyl silyl ethers with aryl-Grinard reagents, where the nickel catalyst l
Regioselective Allylation of a Grignard Reagent Catalysed by Phosphine-Nickel and -Palladium Complexes
Hayashi, Tamio,Konishi, Mitsuo,Yokota, Kan-ichi,Kumada, Makoto
, p. 313 - 314 (2007/10/02)
Nickel and palladium complexes of the 1,1'-bis(diphenylphosphino)ferrocene ligand effectively catalysed the regioselective cross-coupling of allylic ethers with phenylmagnesium bromide; use of the nickel catalyst leads to carbon-carbon bond formation giving the terminal alkene while the palladium catalyst gives the non-terminal alkene.
