367500-59-2Relevant academic research and scientific papers
Substituted Hantzsch Esters as Versatile Radical Reservoirs in Photoredox Reactions
Gu, Fangjun,Huang, Wenhao,Liu, Xu,Chen, Wenxin,Cheng, Xu
supporting information, p. 925 - 931 (2018/01/04)
Substituted Hantzsch esters can act as radical reservoirs in photoredox reactions, steadily releasing a carbon radical and a hydrogen atom radical in the absence of an additional electron acceptor. We propose that radical release by substituted Hantzsch esters occurs via a mechanism involving an internal redox cycle. Cinnamidecinnamides, styrenes, α,β-unsaturated acids, and diarylethenes could be alkylated smoothly with these reagents. (Figure presented.).
Late-Stage C-H Alkylation of Heterocycles and 1,4-Quinones via Oxidative Homolysis of 1,4-Dihydropyridines
Gutiérrez-Bonet, álvaro,Remeur, Camille,Matsui, Jennifer K.,Molander, Gary A.
supporting information, p. 12251 - 12258 (2017/09/12)
Under oxidative conditions, 1,4-dihydropyridines (DHPs) undergo a homolytic cleavage, forming exclusively a Csp3-centered radical that can engage in the C-H alkylation of heterocyclic bases and 1,4-quinones. DHPs are readily prepared from aldehydes, and considering that aldehydes normally require harsh reaction conditions to take part in such transformations, with mixtures of alkylated and acylated products often being obtained, this net decarbonylative alkylation approach becomes particularly useful. The present method takes place under mild reaction conditions and requires only persulfate as a stoichiometric oxidant, making the procedure suitable for the late-stage C-H alkylation of complex molecules. Notably, structurally complex pharmaceutical agents could be functionalized or prepared with this protocol, such as the antimalarial Atovaquone and antitheilerial Parvaquone, thus evidencing its applicability. Mechanistic studies revealed a likely radical chain process via the formation of a dearomatized intermediate, providing a deeper understanding of the factors governing the reactivity of these radical forebears.
An efficient and fast procedure for the Hantzsch dihydropyridine synthesis under microwave conditions
?hberg,Westman
, p. 1296 - 1298 (2007/10/03)
Abstract: A single-mode microwave cavity synthesizer with temperature and pressure control was used to accelerate the Hantzsch synthesis of 4-aryl and 4-alkyl-2,6-dimethyl-1,4-dihydro-3,5-pyridinedicarboxylates. In comparison with both conventional method
