824-90-8Relevant articles and documents
Trifluoroacetic Acid Catalyzed Allylic Phenylation of α-Methylallyl Acetate, α-Methylallyl Trifluoroacetate, and α-Methylallyl Alcohol with Benzene
Fujiwara, Yuzo,Kuromaru, Hiroaki,Taniguchi, Hiroshi
, p. 4309 - 4310 (1984)
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Quaternary Phosphonium Carboxylates: Structure, Dynamics and Intriguing Olefination Mechanism
Müller-Bunz, Helge,Muldoon, Jimmy,Nikitin, Kirill,Vetter, Anna C.
supporting information, (2022/01/12)
We have earlier shown how the Wittig chemistry can be done using novel Eigenbase phosphonium carboxylate reagents. Here we discuss the phenomenon of ion pairing, their solution tautomerism, solid-state structure, and mechanistic aspects of olefination. The results point to a complex process involving unfamiliar H-bond-driven ion-pair equilibria followed by standard Wittig reaction steps.
Bifunctional Metal-Organic Layers for Tandem Catalytic Transformations Using Molecular Oxygen and Carbon Dioxide
Jiang, Xiaomin,Lan, Guangxu,Lin, Wenbin,Ni, Kaiyuan,Quan, Yangjian,Shi, Wenjie,Song, Yang,Wang, Cheng
supporting information, p. 16718 - 16724 (2021/10/21)
Tandem catalytic reactions improve atom- and step-economy over traditional synthesis but are limited by the incompatibility of the required catalysts. Herein, we report the design of bifunctional metal-organic layers (MOLs), HfOTf-Fe and HfOTf-Mn, consisting of triflate (OTf)-capped Hf6 secondary building units (SBUs) as strong Lewis acidic centers and metalated TPY ligands as metal active sites for tandem catalytic transformations using O2 and CO2 as coreactants. HfOTf-Fe effectively transforms hydrocarbons into cyanohydrins via tandem oxidation with O2 and silylcyanation whereas HfOTf-Mn converts styrenes into styrene carbonates via tandem epoxidation and CO2 insertion. Density functional theory calculations revealed the involvement of a high-spin FeIV (S = 2) center in the challenging oxidation of the sp3 C-H bond. This work highlights the potential of MOLs as a tunable platform to incorporate multiple catalysts for tandem transformations.
Boosting Conjugate Addition to Nitroolefins Using Lithium Tetraorganozincates: Synthetic Strategies and Structural Insights
Dell'Aera, Marzia,Perna, Filippo Maria,Vitale, Paola,Altomare, Angela,Palmieri, Alessandro,Maddock, Lewis C. H.,Bole, Leonie J.,Kennedy, Alan R.,Hevia, Eva,Capriati, Vito
supporting information, p. 8742 - 8748 (2020/07/04)
We report the first transition metal catalyst- and ligand-free conjugate addition of lithium tetraorganozincates (R4ZnLi2) to nitroolefins. Displaying enhanced nucleophilicity combined with unique chemoselectivity and functional group tolerance, homoleptic aliphatic and aromatic R4ZnLi2 provide access to valuable nitroalkanes in up to 98 % yield under mild conditions (0 °C) and short reaction time (30 min). This is particularly remarkable when employing β-nitroacrylates and β-nitroenones, where despite the presence of other electrophilic groups, selective 1,4 addition to the C=C is preferred. Structural and spectroscopic studies confirmed the formation of tetraorganozincate species in solution, the nature of which has been a long debated issue, and allowed to unveil the key role played by donor additives on the aggregation and structure of these reagents. Thus, while chelating N,N,N’,N’-tetramethylethylenediamine (TMEDA) and (R,R)-N,N,N’,N’-tetramethyl-1,2-diaminocyclohexane (TMCDA) favour the formation of contacted-ion pair zincates, macrocyclic Lewis donor 12-crown-4 triggers an immediate disproportionation process of Et4ZnLi2 into equimolar amounts of solvent-separated Et3ZnLi and EtLi.