37812-49-0Relevant articles and documents
Minimization of Back-Electron Transfer Enables the Elusive sp3 C?H Functionalization of Secondary Anilines
Zhao, Huaibo,Leonori, Daniele
, p. 7669 - 7674 (2021/03/08)
Anilines are some of the most used class of substrates for application in photoinduced electron transfer. N,N-Dialkyl-derivatives enable radical generation α to the N-atom by oxidation followed by deprotonation. This approach is however elusive to monosubstituted anilines owing to fast back-electron transfer (BET). Here we demonstrate that BET can be minimised by using photoredox catalysis in the presence of an exogenous alkylamine. This approach synergistically aids aniline SET oxidation and then accelerates the following deprotonation. In this way, the generation of α-anilinoalkyl radicals is now possible and these species can be used in a general sense to achieve divergent sp3 C?H functionalization.
Ruthenium N-Heterocyclic Carbene Complexes for Chemoselective Reduction of Imines and Reductive Amination of Aldehydes and Ketones
Kathuria, Lakshay,Samuelson, Ashoka G.
, (2020/06/17)
Chemoselective reduction of imines to secondary amines is catalyzed efficiently by tethered and untethered, half-sandwich ruthenium N-heterocyclic carbene (NHC) complexes at room temperature. The untethered Ru-NHC complexes are more efficient as catalysts for the reduction of aldimines and ketimines than the tethered complexes. Using the best untethered complex as a catalyst, electronic and steric demands on the reaction was probed using a series of imines. Chemoselectivity of the catalyst towards imine reduction was tested by performing inter and intramolecular competitive reactions in a variety of ways. The catalyst exhibits a very high TON and TOF under anaerobic conditions.
In water alkylation of amines with alcohols through a borrowing hydrogen process catalysed by ruthenium nanoparticles
Risi, Caterina,Calamante, Massimo,Cini, Elena,Faltoni, Valentina,Petricci, Elena,Rosati, Filippo,Taddei, Maurizio
supporting information, p. 327 - 331 (2020/02/13)
A simple and environmentally benign procedure for the synthesis of secondary amines in water has been developed. Combining Ru3(CO)12, tetraphenylcyclopentadienone and a small quantity of TGPS-750-M surfactant, primary and secondary alcohols were alkylated at N employing equimolar amounts of aromatic amines in water. The reaction occurs under microwave (MW) dielectric heating with high conversion and high yield. When required, the use of biomass-derived 2-MeTHF or GVL as a co-solvent is possible. Under the influence of MWs, a Ru nanoparticle-nanomicelle combination was formed acting as an effective and recyclable catalyst. This protocol was also employed for "in water" cyclisation to synthesise biologically relevant pyrrolobenzodiazepines (PBDs).
