25944-71-2Relevant articles and documents
New NLO stilbene derivatives bearing phosphonate ester electron-withdrawing groups
Belfield, Kevin D.,Chinna, Chandrasekhar,Schafer, Katherine J.
, p. 6131 - 6134 (1997)
The synthesis and characterization of a new class of electron donor-acceptor substituted stilbenes hearing a phosphonate ester as the electron-withdrawing functionality is described. Phosphorylation of aromatic rings was accomplished using Ni-catalyzed Arbuzov reactions, while Pd-catalyzed Heck-type coupling reactions were employed to construct the stilbene derivatives. Through determination of an electro-optic coefficient (r33), it was demonstrated that the phosphonate ester group is effective as an electron-withdrawing group for stilbene-based second-order NLO materials.
Visible-light-mediated phosphonylation reaction: formation of phosphonates from alkyl/arylhydrazines and trialkylphosphites using zinc phthalocyanine
Hosseini-Sarvari, Mona,Koohgard, Mehdi
, p. 5905 - 5911 (2021/07/12)
In this work, we developed a ligand- and base-free visible-light-mediated protocol for the photoredox syntheses of arylphosphonates and, for the first time, alkyl phosphonates. Zinc phthalocyanine-photocatalyzed Csp2-P and Csp3-P bond formations were efficiently achieved by reacting aryl/alkylhydrazines with trialkylphosphites in the presence of air serving as an abundant oxidant. The reaction conditions tolerated a wide variety of functional groups.
A case of chain propagation: α-aminoalkyl radicals as initiators for aryl radical chemistry
Constantin, Timothée,Juliá, Fabio,Leonori, Daniele,Sheikh, Nadeem S.
, p. 12822 - 12828 (2020/12/29)
The generation of aryl radicals from the corresponding halides by redox chemistry is generally considered a difficult task due to their highly negative reduction potentials. Here we demonstrate that α-aminoalkyl radicals can be used as both initiators and chain-carriers for the radical coupling of aryl halides with pyrrole derivatives, a transformation often employed to evaluate new highly reducing photocatalysts. This mode of reactivity obviates for the use of strong reducing species and was also competent in the formation of sp2 C-P bonds. Mechanistic studies have delineated some of the key features operating that trigger aryl radical generation and also propagate the chain process.
