62506-88-1Relevant articles and documents
Vanadium-and chromium-catalyzed dehydrogenative synthesis of imines from alcohols and amines
Madsen, Robert,Miao, Yulong,Samuelsen, Simone V.
supporting information, p. 1328 - 1335 (2021/05/29)
Vanadium(IV) tetraphenylporphyrin dichloride and chromium(III) tetraphenylporphyrin chloride have been developed as catalysts for the acceptorless dehydrogenation of alcohols. The catalysts have been applied to the direct synthesis of imines in overall good yields from a variety of alcohols and amines. The transformations are proposed to proceed by metal?ligand bifunctional pathways with an outer-sphere transfer of two hydrogen atoms from the alcohol to the metal porphyrin complexes. The results show that vanadium and chromium catalysts can also be employed for the dehydrogenation of alcohols with the release of hydrogen gas, and they may represent valuable alternatives to other catalysts based on Earth-abundant metals.
Dehydrogenative amide synthesis from alcohols and amines utilizing N-heterocyclic carbene-based ruthenium complexes as efficient catalysts: The influence of catalyst loadings, ancillary and added ligands
Wang, Wan-Qiang,Wang, Zhi-Qin,Sang, Wei,Zhang, Rui,Cheng, Hua,Chen, Cheng,Peng, Da-Yong
, (2021/01/05)
The metal-catalyzed dehydrogenative coupling of alcohols and amines to access amides has been recognized as an atom-economic and environmental-friendly process. Apart from the formation of the amide products, three other kinds of compounds (esters, imines and amines) may also be produced. Therefore, it is of vital importance to investigate product distribution in this transformation. Herein, N-heterocyclic carbene-based Ru (NHC/Ru) complexes [Ru-1]-[Ru-5] with different ancillary ligands were prepared and characterized. Based on these complexes, we selected condition A (without an added NHC precursor) and condition B (with an added NHC precursor) to comprehensively explore the selectivity and yield of the desired amides. After careful evaluation of various parameters, the Ru loadings, added NHC precursors and the electronic/steric properties of ancillary NHC ligands were found to have considerable influence on this catalytic process.
Microwave-assisted synthesis of α-aminophosphonates with sterically demanding α-aryl substituents
Hudson, Harry R.,Tajti, ádám,Bálint, Erika,Czugler, Mátyás,Karaghiosoff, Konstantin,Keglevich, Gy?rgy
, p. 1446 - 1455 (2020/03/16)
A series of N-benzhydryl protected α-aminophosphonates with α-phenyl, α-(1-naphtyl), α-(9-anthryl) or α-(1-pyrenyl) substituents was synthesized by the Kabachnik–Fields condensation of diphenylmethylamine (benzhydrylamine), the corresponding aryl aldehyde and a dialkyl phosphite under MW irradiation. X-ray studies performed at low temperatures for a few of these α-aminophosphonates confirmed the presence of unusually short intramolecular Cα–Hδ+ ··· δ+H–Cperi contacts.