84839-90-7Relevant academic research and scientific papers
A highly practical and general route for α-arylations of ketones using bis-phosphinoferrocene-based palladium catalysts
Grasa, Gabriela A.,Colacot, Thomas J.
, p. 522 - 529 (2013/01/03)
Well-defined, air-stable Pd complexes of bis-phosphinoferrocene family of catalysts have been studied in the arylation of various ketones with aryl chlorides and aryl bromides. Bis(di-tert-butyl)phosphinoferrocene (DtBPF)-based catalysts such as (DtBPF) P
α-arylation of ketones using highly active, air-stable (DtBPF)PdX2 (X = Cl, Br) catalysts
Grasa, Gabriela A.,Colacot, Thomas J.
, p. 5489 - 5492 (2008/09/19)
α-Arylation of various ketones with aryl chlorides and bromides using the well-defined and air-stable (DtBPF)PdX2 (X = Cl, Br) catalysts gave 80-100% yield of the coupled products under relatively mild conditions at low catalyst loadings. The X
Phosphorinanes as ligands for palladium-catalyzed cross-coupling chemistry
Brenstrum, Tim,Clattenburg, Julie,Britten, James,Zavorine, Serguei,Dyck, Jeff,Robertson, Alan J.,McNulty, James,Capretta, Alfredo
, p. 103 - 105 (2007/10/03)
(Chemical Equation Presented) Phosphorinanes are presented as a class of phosphine ligand suitable for organopalladium cross-coupling chemistry. Prepared via a direct double Michael addition of a monoalkyl- or arylphosphine to phorone followed by a Wolf-K
Suzuki-Miyaura, α-ketone arylation and dehalogenation reactions catalyzed by a versatile N-heterocyclic carbene-palladacycle complex
Navarro, Oscar,Marion, Nicolas,Oonishi, Yoshihiro,Kelly III, Roy A.,Nolan, Steven P.
, p. 685 - 692 (2007/10/03)
The activity of the complex (IPr)PdCl(η2-N,C-C 12H7NMe2), 1 [IPr = (N,N′-bis(2,6- diisopropylphenyl)-imidazol)-2-ylidene], in the Suzuki-Miyaura cross-coupling reaction involving unactivated aryl chlorides and triflates with arylboronic acids at room temperature in technical grade 2-propanol is described. These conditions allow for the synthesis of di- and tri-ortho-substituted biaryls in very short reaction times. This complex also displays very high activity for α-ketone arylation and dehalogenation reactions of activated and unactivated aryl chlorides.
(IPr)Pd(acac)Cl: An easily synthesized, efficient, and versatile precatalyst for C-N and C-C bond formation
Marion, Nicolas,Ecarnot, Elise C.,Navarro, Oscar,Amoroso, Dino,Bell, Andrew,Nolan, Steven P.
, p. 3816 - 3821 (2007/10/03)
A very straightforward synthesis of (IPr)Pd(acac)Cl from two commercially available starting materials, Pd(acac)2 and IPr·HCl [acac = acetylacetonate; IPr = N,N′-bis(2,6-diisopropylphenyl)imidazol-2-ylidene], has been developed. The resulting complex, (IPr)Pd(acac)Cl (1), has proven to be a highly active PdII precatalyst in the Buchwald-Hartwig and the α-ketone arylation reactions. A wide range of substrates has been screened, including unactivated, sterically hindered, and heterocyclic aryl chlorides.
NUCLEOPHILIC HETEROCYCLIC CARBENE DERIVATIVES OF PD(ACAC)2 FOR CROSS-COUPLING REACTIONS
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Page/Page column 21, 41-42, 44-45, (2010/11/25)
Embodiments in accordance with the present invention provide for a palladium complex characterized by the general Formula (I): where A is a bidentate monoanionic ligand, NHC is a nucleophilic heterocyclic carbene, and Z is an anionic ligand. Such palladium complexes are useful in initiating cross-coupling reactions.
An efficient and mild protocol for the α-arylation of ketones mediated by an (imidazol-2-ylidene)palladium(acetate) system
Singh, Rohit,Nolan, Steven P.
, p. 5832 - 5840 (2007/10/03)
The activity of well-defined N-heterocyclic carbene (NHC)-palladium acetate complexes has been studied in the α-arylation of ketones. The enolate was generated in situ via use of slight excess of sodium tert-butoxide as base. The results showed a high act
Palladium complexes of 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phenyl-6- phosphaadamantane: Synthesis, crystal structure and use in the Suzuki and Sonogashira reactions and the α-arylation of ketones
Adjabeng, George,Brenstrum, Tim,Frampton, Christopher S.,Robertson, Al J.,Hillhouse, John,McNulty, James,Capretta, Alfredo
, p. 5082 - 5086 (2007/10/03)
Palladium complexes of 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phenyl-6- phosphaadamantane were prepared and characterized with Pd[1,3,5,7-tetramethyl-2, 4,8-trioxa-6-phenyl-6-phosphaadamantane]2·dba shown to be an effective catalyst for use in the
Well-defined, air-stable (NHC)Pd(Allyl)Cl (NHC = N-heterocyclic carbene) catalysts for the arylation of ketones
Viciu, Mihai S.,Germaneau, Romain F.,Nolan, Steven P.
, p. 4053 - 4055 (2007/10/03)
(formula presented) A number of palladium-N-heterocyclic carbene (NHC) complexes were found to be active catalysts for the arylation of ketones. A large number of substrates, both aryl halides and ketones, are compatible with the reaction conditions. The ketone arylation reactions are achieved with low catalyst loading in short reaction times using aryl chlorides and triflates as reactive partners.
Diverse photochemistry of sterically congested α-arylacetophenones: ground-state conformational control of reactivity
Wagner, Peter J.,Zhou, Boli,Hasegawa, Tadashi,Ward, Donald L.
, p. 9640 - 9654 (2007/10/02)
The effects of α and ortho substituents on the photoreactivity of various α-(o-tolyl)- and α-mesitylacetophenones have been measured. In general, both types of substitution lower the efficiency of cyclization to 2-indanol derivatives in solution. 1,3-Rearrangement of an α-mesityl group to group to form enol ethers and α-cleavage to radicals compete to various degrees, in some cases becoming dominant. Quenching studies in solution show that all three reactions occur from the same n,π* triplet state; α-substitution lowers rate constants for δ-hydrogen abstraction and increases those for α-cleavage and 1,3-rearrangement. X-ray crystal analysis and MMX calculations both show that any additional substitution at the α-carbon of α-aryl (phenyl, tolyl, or mesityl) ketones favors conformers in which the α-aryl group have rotated 120° away from eclipsing the carbonyl. In agreement with this, α-phenyl and α-(o-tolyl) ketones undergo γ-hydrogen abstraction (Norrish type II reaction) with rate constants almost as large as those of the nonarylated ketones. NMR line-broadening studies show that, in most of the α-mesityl ketones, the rate constants for rotation around the mesityl-α-carbon bond (104-106 s-1) are much slower than triplet decay. The same is true for rotations around the carbonyl-α-carbon bond in the α-arylisobutyrophenones. Considered of the spectroscopic evidence, triplet lifetimes, and calculated rotational barriers indicates that ground-state conformational preferences determine which excited-state reactions can occur in most of these ketones. Many of the ketones that cyclize in low yield in solution do so in much higher yield when irradiated as solids, presumably because α-cleavage to radicals becomes mostly revertible. The solid-state reactivity demonstrates that hydrogen abstraction can occur from what are supposedly nonideal geometries; in particular, large values (60-70°) for the dihedral angle and rate constants for hydrogen abstraction in solution plane of the carbonyl π system. The relationship between this angle and rate constants for hydrogen abstraction in solution is discussed. Rate constants for α-cleavage reveal the separate influences of steric congestion and conjugation of the developing benzyl radicals. The 1,3-aryl migration to oxygen appears to arise from initial CT complexation of the α-aryl to the carbonyl; subsequent bonding of oxygen to the benzene ring apparently relieves steric congestion. The 50:50 initial mixture of Z and E enol ethers suggests that the rearrangement is adiabatic, generating enol ether in its twisted triplet state. A large enhancement of indanol yields by alcoholic solvents is suggested to involve protonation of the same CT complex.
