50390-49-3Relevant academic research and scientific papers
Rhodium-Catalyzed and Chiral Zinc Carboxylate-Assisted Allenylation of Benzamides via Kinetic Resolution
Mao, Ruxia,Zhao, Yanliang,Zhu, Xiaohan,Wang, Fen,Deng, Wei-Qiao,Li, Xingwei
supporting information, p. 7038 - 7043 (2021/09/18)
Enantioenriched allenes are important building blocks. While they have been accessed by other coupling methodologies, enantioenriched allenes have been rarely obtained via C-H activation. In this work, kinetic resolution of tertiary propargyl alcohols as an allenylating reagent has been realized via rhodium(III)-catalyzed C-H allenylation of benzamides. The reaction proceeded efficiently under mild conditions, and both the allenylated products and the propargyl alcohols were obtained in high enantioselectivities with an s-factor of up to 139. The resolution results from bias of the two propargylic substituents and is assisted by a chiral zinc carboxylate additive.
Cp?Co(III)-Catalyzed C-H Alkylation with Maleimides Using Weakly Coordinating Carbonyl Directing Groups
Mandal, Rajib,Emayavaramban, Balakumar,Sundararaju, Basker
supporting information, p. 2835 - 2838 (2018/05/29)
A novel protocol for ortho-C-H alkylation of aromatic and heteroaromatic ketones and esters under Cp?Co(III) catalysis has been developed for the first time. The reaction proceeds through initial cyclometalation via weak chelation-assisted C-H bond activation, followed by coordination of activated alkene, insertion between Co-C, and protodemetalation.
Indium-mediated regioselective synthesis of ketones from arylstannanes under solvent-free ultrasound irradiation
Lo Fiego, Marcos J.,Badajoz, Mercedes A.,Domini, Claudia,Chopa, Alicia B.,Lockhart, María T.
, p. 826 - 832 (2013/03/14)
The solvent-free indium-promoted reaction of alkanoyl chlorides with sterically and electronically diverse arylstannanes is a simple and direct method for the regioselective synthesis of primary, secondary and tertiary alkyl aryl ketones in good to excellent isolated yields (42-84%) under mild and neutral conditions. The protocol is also adequate for the synthesis of aryl vinyl ketones. Reaction times are drastically reduced (from 3-32 h to 10-70 min) under ultrasonic irradiation. Evidences for the involvement of a homolytic aromatic ipso-substitution mechanism, in which indium metal acts as radical initiator, are presented. It is possible the transference of two aryl groups from tin, thus improving effective mass yield, working with diarylstannanes as starting substrates.
Catalyst-free alkanoylation of aromatic rings via arylstannanes. Scope and limitations
Lo Fiego, Marcos J.,Lockhart, María T.,Chopa, Alicia B.
supporting information; experimental part, p. 3674 - 3678 (2010/01/18)
The reaction of alkanoyl chlorides with arylstannanes in 1,2-dichlorobenzene (180 °C) is a simple and direct route for the catalyst-free and regioselective synthesis of tertiary alkyl aryl ketones in good to excellent isolated yields (55-77%). Nevertheles
NEW WAYS OF GENERATING ORGANOTIN REACTIVE INTERMEDIATES FOR ORGANIC SYSNTHESIS
Neumann, Wilhelm P.,Hillgaertner, Horst,Baines, Kim M.,Dicke, Rita,Vorspohl, Klaus,et al.
, p. 951 - 960 (2007/10/02)
Progress in generating and applying two important organotin reactive species for organic synthesis is reported. - Stannyl radicals R3Sn., at present the most used tools for free radical synthesis of complicated target molecules, are generally obtained from the hydrides R3SnH.In a number of cases, however, this is a drawback because of the high radical scavenging power of the latter.New ways of generating R3Sn., decoupling them from the presence of R3SnH, are developed and discussed: the spontaneous thermal dissociation of distannanes with bulky substituents, the thermal fragmentation of bistannyl benzpinacols, the ketone sensitized mild photolysis of simple distannanes, and the mild photolysis of benzyltin compounds such as 9-stannyl-9,10-dihydro anthracene.Examples of advantageous applications, also in combinations with adjusted H donors, are given. - Stannyl cations R3Sn(+) are used as superior leaving groups in electrophilic aromatic ipso substitution.Examples for their application under very mild conditions include the considerable broadening of the scope of the Friedel-Crafts acylation, the Vilsmeier formylation, sulfinations, and sulfonations.The directing influence of certain other substituents can be overcome by this ipso substitution.
