14752-72-8Relevant articles and documents
Iodine-mediated 1,2-aryl migration of primary benzhydryl amines
Chang, Junbiao,Du, Yangxu,Hao, Wei,Hou, Jiao,Lu, Qing,Yu, Wenquan
supporting information, p. 16223 - 16226 (2021/09/22)
An iodine-mediated 1,2-aryl migration reaction of primary benzhydryl amines under transition metal-free conditions has been achieved. The crude imines generated by this rearrangement reaction can be directly transformed into various aromatic secondary ami
Towards the rational design of ylide-substituted phosphines for gold(i)-catalysis: From inactive to ppm-level catalysis
Handelmann, Jens,Babu, Chatla Naga,Steinert, Henning,Schwarz, Christopher,Scherpf, Thorsten,Kroll, Alexander,Gessner, Viktoria H.
, p. 4329 - 4337 (2021/04/12)
The implementation of gold catalysis into large-scale processes suffers from the fact that most reactions still require high catalyst loadings to achieve efficient catalysis thus making upscaling impractical. Here, we report systematic studies on the impa
Iron-catalysed 1,2-aryl migration of tertiary azides
Wei, Kaijie,Yang, Tonghao,Chen, Qing,Liang, Siyu,Yu, Wei
, p. 11685 - 11688 (2020/10/19)
1,2-Aryl migration of α,α-diaryl tertiary azides was achieved by using the catalytic system of FeCl2/N-heterocyclic carbene (NHC) SIPr·HCl. The reaction generated aniline products in good yields after one-pot reduction of the migration-resultant imines.
Multicomponent Pyrazole Synthesis from Alkynes, Nitriles, and Titanium Imido Complexes via Oxidatively Induced N-N Bond Coupling
Pearce, Adam J.,Harkins, Robin P.,Reiner, Benjamin R.,Wotal, Alexander C.,Dunscomb, Rachel J.,Tonks, Ian A.
supporting information, p. 4390 - 4399 (2020/03/04)
Pyrazoles are an important class of heterocycles found in a wide range of bioactive compounds and pharmaceuticals. Pyrazole synthesis often requires hydrazine or related reagents where an intact N-N bond is conservatively installed into a pyrazole precursor fragment. Herein, we report the multicomponent oxidative coupling of alkynes, nitriles, and Ti imido complexes for the synthesis of multisubstituted pyrazoles. This modular method avoids potentially hazardous reagents like hydrazine, instead forming the N-N bond in the final step via oxidation-induced coupling on Ti. The mechanism of this transformation has been studied in-depth through stoichiometric reactions of the key diazatitanacyclohexadiene intermediate, which can be accessed via multicomponent coupling of Ti imidos with nitriles and alkynes, ring opening of 2-imino-2H-azirines, or direct metalation of 4-azadiene-1-amine derivatives. The critical transformation in this reaction is the 2-electron oxidation-induced N-N coupling on Ti. This is a rare example of formal N-N coupling on a metal center, which likely occurs through an electrocyclic mechanism analogous to a Nazarov cyclization. Conveniently, these 2-electron-oxidized diazatitanacyclohexadiene intermediates can be accessed via disproportionation of the 1-electron-oxidized species, which allows utilization of weak oxidants such as TEMPO
Cu/Ni-doped sulfated zirconium oxide immobilized on CdFe2O4 NPs: a cheap, sustainable and magnetically recyclable inorgano-catalyst for the efficient preparation of α-aminonitriles in aqueous media
Nasseri, Mohammad Ali,Ramezani-Moghadam, Simin,Kazemnejadi, Milad,Allahresani, Ali
, p. 4233 - 4256 (2020/07/08)
Abstract: A new multifunctional bimetallic nanocatalyst was prepared by immobilization of Cu/Ni-doped sulfated zirconium oxide on magnetic cadmium ferrite (CdFe2O4@SiO2@ZrO2/SO42?/Cu/Ni) and used as an efficient recyclable catalyst for one-pot as well as stepwise preparation of α-aminonitriles under mild conditions. The magnetic nanocatalyst was characterized by FTIR, TGA, VSM, XRD, EDX, FE-SEM, and TEM analyses. Also, the surface acidity of the catalyst was measured by pyridine adsorption assay. The catalyst possesses various active sites which could catalyst a variety of aromatic and aliphatic aldehydes to the corresponding α-amionitriles under moderate to high yields in the presence of aniline. Furthermore, transformation of ketones to the desired α-amionitriles and some bis-aminonitriles was also performed by this method. The catalyst could be readily recovered from the reaction mixture and reused for several times without significant loss of activity. Graphic abstract: A general and efficient method has been developed for transformation of a variety of aliphatic, aromatic aldehydes and ketones to the corresponding α-aminonitriles using a multifunctional recyclable CdFe2O4@SiO2@ZrO2/SO42?/Cu/Ni nanocatalyst.[Figure not available: see fulltext.]
A silica-supported titanium catalyst for heterogeneous hydroamination and multicomponent coupling reactions
Aldrich, Kelly E.,Odom, Aaron L.
, p. 11352 - 11360 (2019/08/07)
Highly dehydrated silica gel, SiO2700, gave a material with a total surface hydroxyl density of 0.31 ± 0.05 mmol g-1, 0.9 ± 0.1 Si-OH sites per nm2. Treatment of this material with Ti(NMe2)4/sub
Mono- and diylide-substituted phosphines (YPhos): Impact of the ligand properties on the catalytic activity in gold(i)-catalysed hydroaminations
Schwarz, Christopher,Handelmann, Jens,Baier, Daniel M.,Ouissa, Alina,Gessner, Viktoria H.
, p. 6808 - 6815 (2019/12/03)
Understanding the impact of ligand properties on their performance in catalysis is seminal for future ligand design and catalyst improvement. In this work, the influence of the steric and electronic properties on the efficiency of a series of mono- and di
Synthesis and application of axially chiral biscarbolines with functional N-O and sulfone for 1,2-transfer hydrogenations of ketimines
Xing, Yongfei,Wu, Shijie,Dong, Mengxian,Wang, Jie,Liu, Li,Zhu, Huajie
supporting information, (2019/08/08)
A series of axially chiral biscarboline-based sulfones were synthesized from L-tryptophane and applied for enantioselective 1,2-transfer hydrogenations of ketimines using trichlorosilane. The catalyst 4e, which had a tertiary butyl group, exhibited a good conversion and high enantioselectivities up to 96%ee in the series of reactions.
Ylide-Functionalized Phosphines: Strong Donor Ligands for Homogeneous Catalysis
Scherpf, Thorsten,Schwarz, Christopher,Scharf, Lennart T.,Zur, Jana-Alina,Helbig, Andreas,Gessner, Viktoria H.
supporting information, p. 12859 - 12864 (2018/09/25)
Phosphines are important ligands in homogenous catalysis and have been crucial for many advances, such as in cross-coupling, hydrofunctionalization, or hydrogenation reactions. Herein we report the synthesis and application of a novel class of phosphines bearing ylide substituents. These phosphines are easily accessible via different synthetic routes from commercially available starting materials. Owing to the extra donation from the ylide group to the phosphorus center the ligands are unusually electron-rich and can thus function as strong electron donors. The donor capacity surpasses that of commonly used phosphines and carbenes and can easily be tuned by changing the substitution pattern at the ylidic carbon atom. The huge potential of ylide-functionalized phosphines in catalysis is demonstrated by their use in gold catalysis. Excellent performance at low catalyst loadings under mild reaction conditions is thus seen in different types of transformations.
P-Stereogenic and Non-P-Stereogenic Ir-MaxPHOX in the Asymmetric Hydrogenation of N -Aryl Imines. Isolation and X-ray Analysis of Imine Iridacycles
Salomó, Ernest,Rojo, Pep,Hernández-Lladó, Pol,Riera, Antoni,Verdaguer, Xavier
, p. 4618 - 4627 (2018/04/26)
A small library of Ir-MaxPHOX catalysts has been applied to the asymmetric hydrogenation of N-aryl imines. A structure-activity analysis of the three-chiral-center MaxPHOX ligand has been performed. Using complex 1b, the hydrogenation of N-aryl imines too
