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1.
Pei‐Fang Li Cheng‐Bo Yi Shu‐Jian Ren Jin Qu 《Advanced Synthesis \u0026amp; Catalysis》2016,358(13):2088-2092
A divergent approach to generate either 1‐hydroxymethylindenes (which could then be converted to benzofulvenes through a dehydration reaction) or naphthalenes by the rearrangement of cycloprop[2,3]inden‐1‐ols is reported. The effect of the cyclopropyl ring substitution pattern on ring‐opening/expansion rearrangements of the substrates was systemically studied.
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This paper describes the aerobic oxidation of styrenes catalyzed by iron(III) chloride (FeCl3) to form β‐keto‐N‐alkoxyphthalimides in fair to good yields. This oxidative process employs mild conditions with green and atom efficient dioxygen (O2) as the oxidant.
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Jian Li Yin‐Long Li Nan Jin Ai‐Lun Ma Ya‐Nan Huang Jun Deng 《Advanced Synthesis \u0026amp; Catalysis》2015,357(11):2474-2478
A practical and novel process for the decarboxylative fluorination of β‐ketoacids in water in the presence of phase transfer catalyst has been developed, affording a series of α‐fluoroketones in good to excellent yields. Furthermore, a preliminary investigation for the catalytic asymmetric transformation was performed and a proposed mechanistic pathway for this catalytic process was proposed.
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Sodium Iodide/tert‐Butyl(dimethyl)silyl Chloride‐Induced Isomerization of 2,3‐Allenols to 2(E)‐Enals
Rong Zeng Zhichao Ma Chunling Fu Shengming Ma 《Advanced Synthesis \u0026amp; Catalysis》2014,356(6):1343-1358
Through an unexpected CC bond migration, 2(E)‐enals were efficiently prepared highly stereoselectively in moderate to good yields via the sodium iodide/tert‐butyl(dimethyl)silyl chloride (NaI/TBSCl)‐mediated reaction of the easily available 2,3‐allenols. Based on a careful mechanistic study, including control experiments and deuterium‐labeling experiments, an electron‐withdrawing substituent group in the 4 position has been proven to be crucial and a possible mechanism has been proposed.
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Joanna Hejmanowska Anna Albrecht Jakub Pita ukasz Albrecht 《Advanced Synthesis \u0026amp; Catalysis》2015,357(18):3843-3848
An organocatalytic approach for the stereoselective synthesis of 3,4‐dihydrocoumarins with an α,α‐disubstituted amino acid moiety incorporated is presented. The developed methodology is based on the cascade reaction between α‐substituted azlactones and 2‐hydroxychalcones. It is initiated by a chiral Brønsted base‐catalyzed enantio‐ and diastereoselective Michael reaction followed by the azlactone ring opening to construct a 3,4‐dihydrocoumarin framework. Products bearing two adjacent stereogenic centers, one being quaternary, were formed with high enantioselectivities and excellent diastereoselectivities. Furthermore, the complete regioselectivity of the new cascade reactivity is worthy of notice.
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Yaping Wang Xinjian Li Faqiang Leng Helong Zhu Jingya Li Dapeng Zou Yangjie Wu Yusheng Wu 《Advanced Synthesis \u0026amp; Catalysis》2014,356(16):3307-3313
An efficient and practical decarboxylative double benzylation method for various 2‐picolinic acids has been established by using a bimetallic catalytic system of palladium(II) chloride (PdCl2) and silver(I) oxide (Ag2O), which offered a variety of diarylmethane derivatives with moderate to good yields.
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Liangbin Huang Qian Wang Wanqing Wu Huanfeng Jiang 《Advanced Synthesis \u0026amp; Catalysis》2014,356(9):1949-1954
This paper describes two efficient strategies to suppress β‐H elimination during the palladium/copper bimetallic system‐mediated cross‐coupling between alkynamides and alkenes. Remote donor groups with the terminal olefins, such as toluenesulfonamide, phosphate, sulfone, etc., cooperate with the amide of alkynamides and chelate the palladium active center, to promote C(sp3) O bond formation by suppressing the β‐H elimination. Another strategy uses the rigid structure of norbornene to make an intermediate without a syn‐β‐hydrogen to achieve reductive elimination of the C Cl bond.
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Cheonhyoung Park Min Woo Ha Byungsoo Kim Suckchang Hong Doyoung Kim Yohan Park Mi‐hyun Kim Jae Kyun Lee Jeeyeon Lee Hyeung‐geun Park 《Advanced Synthesis \u0026amp; Catalysis》2015,357(13):2841-2848
A new enantioselective synthetic method for the synthesis of α,α‐dialkylmalonates with a quaternary carbon center was developed via α‐alkylation of prochiral malonates by phase‐transfer catalysis (PTC). Asymmetric α‐alkylation of benzylideneamino tert‐butyl α‐methylmalonates under phase‐transfer catalytic conditions in the presence of (S,S)‐3,4,5‐trifluorophenyl‐NAS bromide afforded the corresponding α,α‐dialkylmalonates in high yields (up to 97%) with excellent enantioselectivities (up to 98% ee). The products were then selectively hydrolyzed to chiral malonic monoacids under basic, acidic, or catalytic hydrogenation conditions.
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《Advanced Synthesis \u0026amp; Catalysis》2009,351(6):805-805
The cover picture, provided by Maurice S. Brookhart, shows an example of a cationic palladium diimine complex which catalyzes polymerization of ethylene to high molecular weight, highly branched polyethylene. The catalyst resting states are the alkyl ethylene complexes as modeled by the ethyl ethylene complex shown. Migratory insertion of these alkyl ethylene species leads to β‐agostic complexes in which palladium can rapidly migrate along the chain (“chain‐walking”) through β‐elimination/readdition reactions. Trapping of branched alkyl complexes followed by insertion leads to formation of branches in the polymer chain. Polyethylenes formed exhibit branches‐on‐branches since chain‐walking through tertiary centers is facile.
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《Advanced Synthesis \u0026amp; Catalysis》2009,351(3):289-289
The cover picture, provided by Maurice S. Brookhart, shows an example of a cationic palladium diimine complex which catalyzes polymerization of ethylene to high molecular weight, highly branched polyethylene. The catalyst resting states are the alkyl ethylene complexes as modeled by the ethyl ethylene complex shown. Migratory insertion of these alkyl ethylene species leads to β‐agostic complexes in which palladium can rapidly migrate along the chain (“chain‐walking”) through β‐elimination/readdition reactions. Trapping of branched alkyl complexes followed by insertion leads to formation of branches in the polymer chain. Polyethylenes formed exhibit branches‐on‐branches since chain‐walking through tertiary centers is facile.
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Eleonora Gianolio Resmi Mohan Albrecht Berkessel 《Advanced Synthesis \u0026amp; Catalysis》2016,358(1):30-33
The dynamic kinetic resolution of α‐substituted racemic β‐lactams by alcoholytic ring‐opening, catalyzed by immobilized lipase B from Candida antarctica is described. With this process, a variety of racemic α‐substituted N‐Cbz‐azetidinones (Cbz=benzyloxycarbonyl) was transformed to the corresponding N‐Cbz‐protected β2‐amino acid allyl esters with high enantioselectivity (up to 99%) and high yields (up to quantitative) at room temperature.
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Antonino Ferraro Luca Bernardi Mariafrancesca Fochi 《Advanced Synthesis \u0026amp; Catalysis》2016,358(10):1561-1565
The asymmetric organocatalytic transfer hydrogenation of β‐acylamino and β‐tert‐butyloxycarbonylamino nitroolefins has been successfully realised in excellent enantioselectivities and yields (up to >99% ee, 97% yield) with a simple thiourea catalyst and a Hantzsch ester as hydrogen source, giving a direct access to enantiomerically pure β‐amino nitroalkanes.
14.
An intramolecular imination/azidation sequence has been realized through the tetrakis(acetonitrile)copper(I) hexafluorophophate [Cu(CH3CN)4PF6]‐catalyzed reaction of γ,δ‐unsaturated ketone O‐benzoyl oximes with trimethylsilyl azide (TMSN3). The reaction proceeds via the copper‐mediated N O cleavage and subsequent C N forming 5‐exo cyclization. The thus formed intermediate is then azidated to afford the corresponding dihydropyrrole product. Preliminary mechanistic investigations suggest that the cyclization step does not involve a radical intermediate.
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Wen‐Xing Liu Si‐Kai Chen Jin‐Miao Tian Yong‐Qiang Tu Shao‐Hua Wang Fu‐Min Zhang 《Advanced Synthesis \u0026amp; Catalysis》2015,357(18):3831-3835
A series of new water‐compatible “spiropyrrolidine triazole” catalysts was designed and synthesized. The asymmetric Michael addition of nitromethane and α,β‐unsaturated aldehydes in an aqueous system was investigated to evaluate these new catalysts, and the resulting adducts were obtained with excellent enantioselectivity (up to 95.5% ee) and moderate to good yield (63–88%).
16.
Xiaolin Pan Yong Luo Yechun Ding Xiaona Fan Jie Wu 《Advanced Synthesis \u0026amp; Catalysis》2014,356(5):1072-1078
1‐Bromo‐2‐(cyclopropylidenemethyl)benzenes react with 2‐alkynylphenols under palladium catalysis, leading to indeno[1,2‐c]chromenes in moderate to good yields. The molecular complexity and diversity can be introduced efficiently from easily available starting materials.
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Liang‐Hua Zou Daniel L. Priebbenow Long Wang Jakob Mottweiler Carsten Bolm 《Advanced Synthesis \u0026amp; Catalysis》2013,355(13):2558-2563
A method to access α‐thioaryl ketones and α‐thioaryl esters employing copper acetate (hydrate) as catalyst and readily accessible diaryl disulfides and β‐diketones (or β‐keto esters) has been developed. Both alkyl‐ and aryl‐substituted carbonyl compounds can be prepared.
20.
Meng Sun Le‐Kai Hou Xiang‐Xiang Chen Xiao‐Juan Yang Wei Sun Yu‐Shi Zang 《Advanced Synthesis \u0026amp; Catalysis》2014,356(18):3789-3793
An efficient strategy for the regioselective ortho‐acylation of azoxybenzenes with various aldehydes in the presence of palladium catalysts has been developed and furnishes good to excellent yields. The reaction proceeds smoothly and can tolerate a variety of functional groups.