10289-45-9Relevant articles and documents
Iron-catalyzed cross-coupling reaction of alkyl halides with biphenyl grignard reagent
Dai,Liu,Zhang,Wei,Guan
, p. 6303 - 6305 (2013)
In the presence of a catalytic amount of iron salts and N,N,N',N'-tetramethylethylene diamine as additive, alkyl bromide reacted with biphenyl magnesium bromide to obtain the cross-coupling product in good yields. The suitable amount of catalyst and the additive are 5 % mol (based on alkyl bromide), 1.3 equiv(based on alkyl bromide), respectively. Under the optimal conditions, the yields of the crosscoupling could reach up to 92.3 %.
Thermal transformations of 4-tert-butylbiphenyl
Repkin,Nesterova,Nesterov,Golovin
, p. 149 - 153 (2010)
The thermal stability of 4-tert-butylbiphenyl was studied in the range of 703-763 K. The competition of the cracking and isomerization reactions of alkyl substituents on the aromatic ring of the reactant and its products has been revealed. The kinetic characteristics of the complex of transformations occurring in the system have been determined. Recommendations are provided regarding the conditions for the determination of the critical parameters of 4-tert-butylbiphenyl and for the processing and use of compounds with a tert-butyl moiety in the molecule.
Iron fluoride/N-heterocyclic carbene catalyzed cross coupling between deactivated aryl chlorides and alkyl grignard reagents with or without β-hydrogens
Agata, Ryosuke,Iwamoto, Takahiro,Nakagawa, Naohisa,Isozaki, Katsuhiro,Hatakeyama, Takuji,Takaya, Hikaru,Nakamura, Masaharu
, p. 1733 - 1740 (2015)
High-yielding cross-coupling reactions of various combinations of aryl chlorides and alkyl Grignard reagents have been developed by using an iron(III) fluoride/1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene (SIPr) catalyst composite. The iron(III) fluoride/SIPr-catalyzed aryl-alkyl coupling demonstrates unprecedented scope for both aryl chlorides and alkyl Grignard reagents, thus enabling the first efficient coupling of electron-rich (deactivated) aryl chlorides with alkyl Grignard reagents without β-hydrogens. The present reaction is also effective for diverse alkyl Grignard reagents such as (trimethylsilyl)methyl, primary, and secondary alkyl Grignard reagents.
Synthesis method of 4-alkyl biphenylacetylene
-
Paragraph 0045-0046, (2021/06/13)
The invention discloses a synthesis method of 4-alkyl biphenyl acetylene. The synthesis method comprises the following steps: carrying out catalytic hydrogenation reaction on 4-alkyl diketone to obtain 4-alkyl biphenyl; then reacting the 4-alkyl biphenyl with halogen to obtain 4-halogen-4 '-alkyl biphenyl; and allowing 4-halo-4 '-alkyl biphenyl and an ethynylation reagent to be subjected to a coupling reaction to obtain a compound shown in a formula (IV) under the action of alkali. The method creatively adopts a palladium catalyst and lewis acid combined catalytic system to carry out deoxidation reaction on 4-alkyl diketone, and has good selectivity and high yield; in addition, hydrogen is used as a hydrogen source, a byproduct is only water, and the method is environment-friendly.
Nickel-catalyzed reductive deoxygenation of diverse C-O bond-bearing functional groups
Cook, Adam,MacLean, Haydn,St. Onge, Piers,Newman, Stephen G.
, p. 13337 - 13347 (2021/11/20)
We report a catalytic method for the direct deoxygenation of various C-O bond-containing functional groups. Using a Ni(II) pre-catalyst and silane reducing agent, alcohols, epoxides, and ethers are reduced to the corresponding alkane. Unsaturated species including aldehydes and ketones are also deoxygenated via initial formation of an intermediate silylated alcohol. The reaction is chemoselective for C(sp3)-O bonds, leaving amines, anilines, aryl ethers, alkenes, and nitrogen-containing heterocycles untouched. Applications toward catalytic deuteration, benzyl ether deprotection, and the valorization of biomass-derived feedstocks demonstrate some of the practical aspects of this methodology.
Preparation of a magnetic and recyclable superparamagnetic silica support with a boronic acid group for immobilizing Pd catalysts and its applications in Suzuki reactions
Aschenaki, Assefa,Bao, James Jianmin,Jia, Wenhui,Li, Youxin,Liu, Jia,Ren, Fangfang,Song, Qianyi,Zheng, Wenqing
, p. 33692 - 33702 (2021/12/07)
Palladium is one of the best metal catalysts for Suzuki cross-coupling reaction to synthesize unsymmetrical biaryl compounds. However, homogeneous palladium (Pd) is limited in an industrial scale due to the high cost, separation, removal, and recovery issues. In this paper, a novel, high activity magnetic nanoparticles (Fe3O4@SiO2-APBA-Pd) catalyst was prepared by a simple, cost-effective procedure. The as-prepared functional nanoparticles (Fe3O4@SiO2-APBA) with boric acid group immobilized Pd through adding Pd(OAc)2 to Fe3O4@SiO2-APBA in absolute ethanol and maintaining for a certain time under a nitrogen atmosphere. The as-prepared catalyst was characterized by FT-IR, SEM, EDX, TEM, ICP-MS, XPS, and XRD. The results showed that the Pd (0.2-0.6 nm) was successfully anchored on the magnetic silica material with boric acid group. The amount of Pd was 0.800 mmol g-1. This magnetic nanostructure (8-15 nm) is especially beneficial as a nanocatalyst because each nanoparticle can catalyze a reaction in a certain time without steric restriction, which could effectively improve the reaction efficiency. The current nanoparticles with the Pd catalyst could be used as a novel, green, and efficient heterogeneous catalyst for Suzuki reactions. This catalyst showed promising catalytic activity and excellent yields toward 14 kinds of Suzuki coupling reactions under mild reaction conditions, which was similar to homogeneous Pd and many reported heterogeneous Pd catalysts. In addition, the turnover number (TON) and turnover frequency (TOF) for the Suzuki reaction were high. TOF and TON were 9048 h-1 and 20?250 for the Suzuki reaction of bromobenzene and phenylboronic acid. Furthermore, the nanoparticles could be easily separated by a magnet, and could be used repeatedly seven times without any significant loss in activity.
Alkyl Carbagermatranes Enable Practical Palladium-Catalyzed sp2-sp3 Cross-Coupling
Xu, Meng-Yu,Jiang, Wei-Tao,Li, Ying,Xu, Qing-Hao,Zhou, Qiao-Lan,Yang, Shuo,Xiao, Bin
supporting information, p. 7582 - 7588 (2019/05/16)
Pd-catalyzed cross-coupling reactions have achieved tremendous accomplishments in the past decades. However, C(sp3)-hybridized nucleophiles generally remain as challenging coupling partners due to their sluggish transmetalation compared to the C(sp2)-hybridized counterparts. While a single-electron-transfer-based strategy using C(sp3)-hybridized nucleophiles had made significant progress recently, fewer breakthroughs have been made concerning the traditional two-electron mechanism involving C(sp3)-hybridized nucleophiles. In this report, we present a series of unique alkyl carbagermatranes that were proven to be highly reactive in cross-coupling reactions with our newly developed electron-deficient phosphine ligands. Generally, secondary alkyl carbagermatranes show slightly lower, yet comparable activity to its Sn analogue. Meanwhile, primary alkyl carbagermatranes exhibit high activity, and they were also proved stable enough to be compatible with various reactions. Chiral secondary benzyl carbagermatrane gave the coupling product under base/additive-free conditions with its configuration fully inversed, suggesting that transmetalation was carried out in an "SE2(open) Inv" pathway, which is consistent with Hiyama's previous observation. Notably, the cross-coupling of primary alkyl carbagermatranes could be performed under base/additive-free conditions with excellent functional group tolerance and therefore may have potentially important applications such as stapled peptide synthesis.
Deacylative transformations of ketones via aromatization-promoted C–C bond activation
Xu, Yan,Qi, Xiaotian,Zheng, Pengfei,Berti, Carlo C.,Liu, Peng,Dong, Guangbin
, p. 373 - 378 (2019/05/22)
Carbon–hydrogen (C–H) and carbon–carbon (C–C) bonds are the main constituents of organic matter. Recent advances in C–H functionalization technology have vastly expanded our toolbox for organic synthesis1. By contrast, C–C activation methods that enable editing of the molecular skeleton remain limited2–7. Several methods have been proposed for catalytic C–C activation, particularly with ketone substrates, that are typically promoted by using either ring-strain release as a thermodynamic driving force4,6 or directing groups5,7 to control the reaction outcome. Although effective, these strategies require substrates that contain highly strained ketones or a preinstalled directing group, or are limited to more specialist substrate classes5. Here we report a general C–C activation mode driven by aromatization of a pre-aromatic intermediate formed in situ. This reaction is suitable for various ketone substrates, is catalysed by an iridium/phosphine combination and is promoted by a hydrazine reagent and 1,3-dienes. Specifically, the acyl group is removed from the ketone and transformed to a pyrazole, and the resulting alkyl fragment undergoes various transformations. These include the deacetylation of methyl ketones, carbenoid-free formal homologation of aliphatic linear ketones and deconstructive pyrazole synthesis from cyclic ketones. Given that ketones are prevalent in feedstock chemicals, natural products and pharmaceuticals, these transformations could offer strategic bond disconnections in the synthesis of complex bioactive molecules.
A 4 - bromo -4 ' - propyl biphenyl synthesis process (by machine translation)
-
, (2018/07/06)
The invention discloses a 4 - bromo - 4' - propyl biphenyl synthesis process, relates to the technical field of the synthesis, the existing technology solves the harsh reaction conditions, the total yield is low. The invention avoids the need for reaction reducing Huang ultra-high temperature reaction conditions or halogen lithium exchange reaction needs of the ultra-low temperature reaction conditions, without the use of carcinogenic compounds [...], mild reaction conditions, synthetic process conditions can be controlled more easily, is easy to operate, simple in after treatment; synthesis process of the present invention chemical reaction the atom economy is high, compared with the prior process in the 20 - 30% of the total yield, the process overall yield 57%, significantly improves the product yield; the invention the use of a readily available and inexpensive industrial chemicals biphenyl as starting material, the cost is reduced. (by machine translation)
Transition-Metal-Free C-H Arylation of Unactivated Arenes with 8-Hydroxyquinoline as a Promoter
Zheng, Xuehua,Wu, Xu-Nian,Chen, Jing-Yi,Luo, Hai-Bin,Wu, Deyan,Wu, Yinuo
, p. 1721 - 1727 (2018/02/06)
A method for the transition-metal-free direct C-H arylation of unactivated arenes is developed with aryl bromides as substrates and 8-hydroxyquinoline as an efficient promoter. A variety of biaryl compounds with structural diversity are obtained in moderate to high yields. Mechanistic studies reveal that the reaction proceeds via a homolytic aromatic substitution pathway.
