67295-38-9Relevant academic research and scientific papers
Iron-Catalyzed Enantioselective Radical Carboazidation and Diazidation of α,β-Unsaturated Carbonyl Compounds
Dong, Shunxi,Feng, Xiaoming,He, Jun,Liu, Wen,Liu, Xiaohua,Pu, Maoping,Wu, Yun-Dong,Zhang, Tinghui
supporting information, p. 11856 - 11863 (2021/08/16)
Azidation of alkenes is an efficient protocol to synthesize organic azides which are important structural motifs in organic synthesis. Enantioselective radical azidation, as a useful strategy to install a C-N3 bond, remains challenging due to the inherently instability and unique structure of radicals. Here, we disclose an efficient enantioselective radical carboazidation and diazidation of α,β-unsaturated ketones and amides catalyzed by chiral N,N′-dioxide/Fe(OTf)2 complexes. An array of substituted alkenes was transformed to the corresponding α-azido carbonyl derivatives in good to excellent enantioselectivities, benefiting the preparation of chiral α-amino ketones, vicinal amino alcohols, and vicinal diamines. Control experiments and mechanistic studies proved the radical pathway in the reaction process. The DFT calculations showed that the azido transferred to the radical intermediate via an intramolecular five-membered transition state with the internal nitrogen of the Fe-N3 species.
Dual Catalysis Relay: Coupling of Aldehydes and Alkenes Enabled by Visible-Light and NHC-Catalyzed Cross-Double C-H Functionalizations
Liu, Ming-Shang,Min, Lin,Chen, Bi-Hong,Shu, Wei
, p. 9715 - 9721 (2021/08/04)
Direct functionalizations of two distinct inert C-H bonds represent the most ideal ways to construct C-C bonds. Herein, we report an intermolecular vinylation of aldehydes using alkenes as the vinylating reagents through sequential two-fold C-H functionalizations. The merging of visible light and N-heterocyclic carbene catalysis allows for the coupling of alkenes with aldehydes through a dual catalysis relay enabled cross-dehydrogenative coupling mechanism. The use of diphenoquinone is essential for the success of this reaction, which plays an intriguing two-fold role in the reaction, as an electron acceptor as well as a radical reservoir for the radical coupling enabling the C-C forming process.
METHODS OF PREPARING a,?-UNSATURATED OR a-HALO KETONES AND ALDEHYDES
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Paragraph 0150-0154, (2017/07/14)
Copper(II) bromide mediated oxidation of acylated enol and use of the reaction in the synthesis of α,β-unsaturated or α-bromo ketones or aldehydes are disclosed. The method provides an efficient and practical process for manufacturing dehydrohedione (DHH) and many other versatile α,β-unsaturated or α-bromo ketones or aldehydes in large scales to avoid using precious metal compounds.
α,β-Unsaturated ketones via copper(II) bromide mediated oxidation
Sharley, James S.,Collado Pérez, Ana María,Ferri, Estela Espinos,Miranda, Amadeo Fernandez,Baxendale, Ian R.
, p. 2947 - 2954 (2016/05/19)
A protocol for effecting a rapid Saegusa-type oxidation of enol acetates is reported. This new method relies on the in situ elimination of an α-bromo intermediate to generate α,β-unsaturated ketones using copper(II) bromide. The methodology developed was applied to a range of substrates including a cyclohexanone, which could be directly converted to the corresponding phenol derivative. A catalytic system in which a non-masked ketone was successfully oxidised using substoichiometric CuBr2 was also developed as a proof of principle.
Copper-catalysed oxidative Csp3-H methylenation to terminal olefins using DMF
Liu, Jianming,Yi, Hong,Zhang, Xin,Liu, Chao,Liu, Ren,Zhang, Guoting,Lei, Aiwen
supporting information, p. 7636 - 7638 (2014/07/08)
A copper-catalysed direct oxidative Csp3-H methylenation to terminal olefins using DMF as one carbon source was developed. In this reaction, various functional groups were well tolerated, thus providing a simple way to construct arylvinylketones and arylvinylpyridines. The preliminary mechanistic investigations revealed that CH2 was from DMF (N-CH3).
Synthesis of pyrazolines by a site isolated resin-bound reagents methodology
Gembus, Vincent,Bonnet, Jean-Jacquesrouen,Janin, Franoisrouen,Bohn, Pierre,Levacher, Vincent,Briere, Jean-Franois
supporting information; experimental part, p. 3287 - 3293 (2010/08/21)
The elaboration of biologically important 3,4-substituted pyrazolines was achieved by an organocatalysed aza-Michael/transimination domino sequence between hydrazones and enones making use of a mixture of heterogeneous resin-bound acid/base reagents. This methodology nicely illustrates the site isolation concept of supported reagents allowing the simultaneous use of otherwise destructive reactive functionalities. The Royal Society of Chemistry 2010.
