- Revisiting the Addition of in-situ Nucleophiles to Allenic Ketones: An Entry Towards Synthesis of Benzodioxins
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The manuscript delineates a revisit towards regioselective addition of in situ generated negative nucleophiles to allenic ketones in the presence of a base. A wide variety of allenic ketones as well as nucleophiles are viable in this transformation. A dir
- Sahoo, Sushree Ranjan,Sarkar, Debayan
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p. 1727 - 1731
(2020/03/13)
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- A bicyclization reaction with two molecular allenyl ketones and isocyanides: Synthesis of a lactone-containing azaspirocycle derivative
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A novel bicyclization reaction of two molecular allenyl ketones and isocyanides has been disclosed. This strategy allows for the construction of structurally complex spirocyclic lactam-lactone systems in an efficient manner. This protocol also demonstrate
- Yuan, Hongdong,Tang, Chongrong,Su, Shikuan,Cui, Lei,Jia, Xueshun,Li, Chunju,Li, Jian
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p. 7231 - 7234
(2019/07/02)
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- Synthesis of 1,2-allenic ketones through oxidation of homopropargyl alcohols with CrO3(cat.)/TBHP under MWI
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A CrO3 catalyzed oxidation of homopropargyl alcohols with tert-butyl hydroperoxide under microwave irradiation was found to be an efficient and rapid alternative for the preparation of 1,2-allenic ketones. The advantages of this procedure inclu
- Zhang, Xin Ying,Qu, Ying Ying,Wang, Yang Yang,Fan, Xue Sen
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experimental part
p. 268 - 271
(2012/01/30)
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- Tandem reactions of 1,2-allenic ketones leading to substituted benzenes and α,β-unsaturated nitriles
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One-pot double Michael addition/intramolecular aldol reaction/ decarboxylation of 1,2-allenic ketones with cyanoacetate offers an efficient and convenient approach to highly functionalized benzenes. With 2-substituted cyanoacetates, the reaction proceeds via a different tandem process to afford α,β-unsaturated nitriles effectively.
- Zhang, Xinying,Jia, Xuefei,Fang, Liangliang,Liu, Nan,Wang, Jianji,Fan, Xuesen
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supporting information; experimental part
p. 5024 - 5027
(2011/11/12)
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- InI3- or ZnI2-catalyzed reaction of hydroxylated 1,5-allenynes with thiols: A new access to 3,5-disubstituted toluene derivatives
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Transition-metal-activated alkynes or allenes can accept nucleophilic attack and undergo direct addition of the nucleophiles to the unsaturated bonds or trigger subsequent rearrangement reactions. This chemistry has witnessed increasing development in recent years. In this report, we have focused on the metal-catalyzed reactions of a variety of substituted propargyl allenic alcohols and thiophenols using indiumACHTUNGTRENUNG(III) and zinc(II) catalysts, which can activate both the alcohol and alkyne. In this reaction, thio groups play the role of a nucleophile and trigger subsequent rearrangements to give benzene derivatives. The products can be further transformed into various 1,3,5-trisubstituted aromatic compounds by nickel-catalyzed coupling reactions through the cleavage of the C-S bonds.
- Ma, Jie,Peng, Lingling,Zhang, Xiu,Zhang, Zhe,Campbell, Melody,Wang, Jianbo
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p. 2214 - 2220
(2011/06/19)
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- Ru(III)-catalyzed oxidation of homopropargyl alcohols in ionic liquid: an efficient and green route to 1,2-allenic ketones
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An efficient and environmentally benign synthesis of 1,2-allenic ketones via RuCl3-catalyzed oxidation of homopropargyl alcohols in ionic liquid with tert-butyl hydroperoxide (TBHP) as the oxidant was reported for the first time. With its reasonable efficiency and green nature, this oxidation provides a novel alternative route to 1,2-allenic ketones.
- Fan, Xuesen,Qu, Yingying,Wang, Yangyang,Zhang, Xinying,Wang, Jianji
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scheme or table
p. 2123 - 2126
(2010/06/14)
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- C-C-Bond Formation by the Palladium-Catalyzed Cycloisomerization/Dimerization of Terminal Allenyl Ketones: Selectivity and Mechanistic Aspects
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The scope of the palladium-catalyzed cyclization/dimerization of terminal allenyl ketones 1 to the 2,4-disubstituted furans 3 has been investigated. Simplified and improved conditions almost exclusively provided the dimer 3, accompanied by only traces of the easily separable monomer 2. The formation of an isomer of 3, the unconjugated ketone 4, was completeley suppressed. Under these mild conditions, besides the normal functional group tolerance known for palladium-catalyzed reactions, an interesting selectivity was observed with functional groups that are known to react either in palladium-catalyzed reactions or reactions catalyzed by other transition-metals. Thus aryl halides, terminal alkynes, 1,6-enynes, and α-allenic alcohols were tolerated. In the latter example the selective reaction of only one out of two different allenes was achieved. Mechanistic investigation indicated a Pd(II)/Pd(IV)-cycle involving palladium(II)-γ-alkoxyvinylcarbene and furylpalladium(IV) hydride intermediates, although a second pathway for the formation of the dimer 3 which also involves Pd(IV)-intermediates like the 3,4-dimethylenepalladacyclopentane 23 and the 3-methylenepalladacyclobutane-like structure 15 (respectively 25) could not completely be excluded.
- Hashmi, A. Stephen K.,Ruppert, Thorsten L.,Knoefel, Thomas,Bats, Jan W.
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p. 7295 - 7304
(2007/10/03)
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