42332-99-0Relevant articles and documents
Determination of orientational isomerism in rhodium(II) metallopeptides by pyrene fluorescence
Sambasivan, Ramya,Ball, Zachary T.
, p. 8203 - 8206,4 (2012)
Rhodium(II) metallopeptides display useful secondary structure, self-assembly, and catalytic activity. The bis-peptide complexes exhibit subtle orientational isomerism that affects function, but is challenging to characterize. We report that pyrene excime
Isotope Effects and the Nature of Selectivity in Rhodium-Catalyzed Cyclopropanations
Nowlan III, Daniel T.,Gregg, Timothy M.,Davies, Huw M. L.,Singleton, Daniel A.
, p. 15902 - 15911 (2003)
The mechanism of the dirhodium tetracarboxylate catalyzed cyclopropanation of alkenes with both unsubstituted diazoacetates and vinyl- and phenyldiazoacetates was studied by a combination of 13C kinetic isotope effects and density functional th
An Inexpensive and Recyclable Silver-Foil Catalyst for the Cyclopropanation of Alkenes with Diazoacetates under Mechanochemical Conditions
Chen, Longrui,Bovee, Mark O.,Lemma, Betsegaw E.,Keithley, Kimberlee S. M.,Pilson, Sara L.,Coleman, Michael G.,Mack, James
, p. 11084 - 11087 (2015)
The diastereoselective cyclopropanation of various alkenes with diazoacetate derivatives can be achieved under mechanochemical conditions using metallic silver foil and a stainless-steel vial and ball system. This solvent-free method displays analogous reactivity and selectivity to solution-phase reactions without the need for slow diazoacetate addition or an inert atmosphere. The heterogeneous silver-foil catalyst system is easily recyclable without any appreciable loss of activity or selectivity being observed. The cyclopropanation products were obtained with excellent diastereoselectivities (up to 98:2 d.r.) and in high yields (up to 96 %).
Blue light-promoted cyclopropenizations of N-tosylhydrazones in water
Yan, Kaichuan,He, Hua,Li, Jianglian,Luo, Yi,Lai, Ruizhi,Guo, Li,Wu, Yong
supporting information, p. 3984 - 3987 (2021/06/15)
Carbene transfer reactions play an important role in the field of organic synthesis because of their ability to construct a variety of molecules. Herein, we reported on blue light-induced cyclopropenizations of N-tosylhydrazones in water, which avoids the use of expensive metal-based catalysts and toxic organic solvents. This metal-free and operationally simple methodology enable highly efficient cyclopropenizations, X-H insertion reactions, and cyclopropanation under mild reaction conditions.
Room Temperature Coupling of Aryldiazoacetates with Boronic Acids Enhanced by Blue Light Irradiation
da Silva, Amanda F.,Afonso, Marco A. S.,Cormanich, Rodrigo A.,Jurberg, Igor D.
, p. 5648 - 5653 (2020/04/22)
A visible-light-promoted photochemical protocol is reported for the coupling of aryldiazoacetates with boronic acids. This photochemical reaction shows great enhancement compared to the same protocol performed in the absence of light. Except for a few cases, the room temperature coupling in the dark (thermal process) generally does not work. When it does, it is likely to also involve free carbenes as key intermediates. Alternatively, photochemical reactions show a broad scope, can be performed under air and tolerate a wide variety of functional groups. Reaction-evolution monitoring, DFT calculations and control experiments have been used to evaluate the main aspects of this intricate mechanistic scenario. Biologically active molecules Adiphenine, Benactyzine and Aprophen have been prepared as examples of synthetic applications.
Blue Light-promoted Carbene Transfer Reactions of Tosylhydrazones
Xu, Yingying,Lv, Guanghui,Yan, Kaichuan,He, Hua,Li, Jianglian,Luo, Yi,Lai, Ruizhi,Hai, Li,Wu, Yong
supporting information, p. 1945 - 1947 (2020/06/08)
Metal-free photochemical carbene-transfer reactions of tosylhydrazones were developed under blue light irradiation at room temperature. This reaction constructs C?X (X=C, N, O, S) bonds and cyclopropanes from readily available and stable starting material
Blue light-promoted N–H insertion of amides, isatins, sulfonamides and imides into aryldiazoacetates: Synthesis of unnatural α-aryl amino acid derivatives
Okada, Celso Y.,dos Santos, Caio Y.,Jurberg, Igor D.
, (2020/07/03)
A photochemical protocol using blue light allows the N–H insertion of amides, isatins, sulfonamides and imides into aryldiazoacetates to afford the corresponding α-amino esters. This method is experimentally simple, inexpensive and tolerates numerous functional groups, thus allowing the straightforward preparation of a variety of α-aryl amino acid derivatives in good yields.
Synthesis of Chiral Bifunctional NHC Ligands and Survey of Their Utilities in Asymmetric Gold Catalysis
Liu, Yunkui,Wang, Xing-Wang,Zhang, Jun-Qi,Zhang, Liming
supporting information, (2019/08/26)
The synthesis and characterization of the chiral bifunctional NHC ligands based on the imidazo[1,5-a]pyridine (ImPy) scaffold are described. These ligands possess a fluxional biaryl axis and a chiral center. The configurational stability of the biaryl axis in their gold(I) complexes is investigated. The application of these axially chiral ImPy-based AuCl complexes in a series of gold catalysis is explored, and varying degrees of asymmetric induction are observed. In most cases, the ligand (aS,R)-L8-H with its cyclohexyl group pointing to the reaction site and hence exerting asymmetric steric influence is more effective in asymmetric induction.
Bis(imino)pyridine iron complexes for catalytic carbene transfer reactions
Wang, Ban,Howard, Isaac G.,Pope, Jackson W.,Conte, Eric D.,Deng, Yongming
, p. 7958 - 7963 (2019/09/06)
The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor-acceptor diazo compounds. Its broad catalytic capability is demonstrated by a range of metal carbene reactions, from cyclopropanation, cyclopropenation, epoxidation, and Doyle-Kirmse reaction to O-H insertion, N-H insertion, and C-H insertion reactions. The asymmetric cyclopropanation of styrene and methyl phenyldiazoacetate was successfully achieved by the new chiral bis(imino)pyridine iron catalyst, which delivers a new gateway for the development of chiral iron catalysis for metal carbene reactions.
Blue light-promoted photolysis of aryldiazoacetates
Jurberg, Igor D.,Davies, Huw M. L.
, p. 5112 - 5118 (2018/06/12)
Aryldiazoacetates can undergo photolysis under blue light irradiation (460-490 nm) at room temperature and under air in the presence of numerous trapping agents, such as styrene, carboxylic acids, amines, alkanes and arenes, thus providing a straighforward and general platform for their mild functionalization.
