41415-69-4Relevant academic research and scientific papers
Photochemical Functionalization of Heterocycles with EBX Reagents: C?H Alkynylation versus Deconstructive Ring Cleavage**
Voutyritsa, Errika,Garreau, Marion,Kokotou, Maroula G.,Triandafillidi, Ierasia,Waser, Jér?me,Kokotos, Christoforos G.
, p. 14453 - 14460 (2020/10/12)
The development of novel methodologies for the functionalization of saturated heterocycles is highly desirable. Herein, we report a cheap and efficient photochemical method for the C?H functionalization of saturated O-heterocycles, as well as the deconstructive ring-cleavage of S-heterocycles, employing hypervalent iodine alkynylation reagents (ethynylbenziodoxolones, EBX). This photochemical alkynylation is performed utilizing phenylglyoxylic acid as the photoinitiator, leading to the corresponding products in good to high yields, under household fluorescent light bulb irradiation. When O-heterocycles were employed, the expected α-C?H alkynylation took place. In contrast, oxidative ring-opening to form a thioalkyne and an aldehyde was observed with S-heterocycles. Preliminary mechanistic experiments are presented to give first insights into this puzzling divergent reactivity.
Chiral bipyrindine and biquinoline ligands: Their asymmetric synthesis and application to the synthesis of trans-whisky lactone
Ito, Katsuji,Yoshitake, Miwa,Katsuki, Tsutomu
, p. 3905 - 3920 (2007/10/03)
Chiral bipyrindine and biquinoline which have been reported to be efficient ligands for the construction of chiral copper catalysts, were synthesized enantioselectively by using Mn-salen catalyzed asymmetric epoxidation as a key step. Enantioselective synthesis of trans-whisky lactone was then achieved by way of enantiospecific ring expansion reaction of oxetane with a chiral copper catalysts bearing the bipyrindine ligand as a chiral source.
