5883-81-8Relevant articles and documents
BF3·Et2O as a metal-free catalyst for direct reductive amination of aldehydes with amines using formic acid as a reductant
Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
supporting information, p. 5205 - 5211 (2021/07/29)
A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.
Phosphine-Catalyzed Synthesis of Chiral N-Heterocycles through (Asymmetric) P(III)/P(V) Redox Cycling
Lorton, Charlotte,Saleh, Nidal,Voituriez, Arnaud
supporting information, p. 3340 - 3344 (2021/06/26)
Phosphine-catalyzed tandem Michael addition/intramolecular Wittig reactions have been developed for the synthesis of chiral 2,5-dihydro-1H-pyrrole and tetrahydropyridine derivatives. These processes have been rendered catalytic in phosphine, thanks to the in situ reduction of phosphine oxide by phenylsilane. Furthermore, catalytic and asymmetric P(III)/P(V) processes were implemented using enantiopure chiral phosphines.
Iodine-mediated C-N and N-N bond formation: A facile one-pot synthetic approach to 1,2,3-triazoles under metal-free and azide-free conditions
Mani, Geeta Sai,Donthiboina, Kavitha,Shaik, Siddiq Pasha,Shankaraiah, Nagula,Kamal, Ahmed
, p. 27021 - 27031 (2019/09/13)
A novel strategy towards the synthesis of 1,4-disubstituted 1,2,3-triazoles via C-N and N-N bond formation has been demonstrated under transition metal-free and azide-free conditions. These 1,2,3-triazoles were obtained in a regioselective manner from commercially available anilines, aryl alkenes/aryl alkynes and N-tosylhydrazines using I2 under O2 atmosphere. Broad substrate scope, milder reaction conditions, good to moderate yields and clean protocol are the notable features of the method. Moreover, this protocol is amenable for the generation of a library of medicinally important key building blocks.