1377860-94-0Relevant articles and documents
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.
Room-Temperature Decarboxylative Alkynylation of Carboxylic Acids Using Photoredox Catalysis and EBX Reagents
Le Vaillant, Franck,Courant, Thibaut,Waser, Jerome
, p. 11200 - 11204 (2016/07/06)
Alkynes are used as building blocks in synthetic and medicinal chemistry, chemical biology, and materials science. Therefore, efficient methods for their synthesis are the subject of intensive research. Herein, we report the direct synthesis of alkynes fr
Organocatalytic alkynylation of densely functionalized monofluorinated derivatives: C(sp3)-C(sp) coupling
Kamlar, Martin,Putaj, Piotr,Vesely, Jan
, p. 2097 - 2100 (2013/04/24)
Organocatalytic alkynylation of nucleophilic fluorocarbons using hypervalent iodine compounds under cinchona-based catalysis, namely using O-allyl N-anthracenyl cinchona alkaloid derivative II, is described. The reaction gives the final fluoro-propargyl compounds in good to excellent yields (up to 91%) and with moderate to low enantioselectivity (up to 61% ee). The reaction represents the first example of the use of hypervalent iodine compounds for the construction of fluorinated compounds and opens access to the preparation of biologically attractive compounds such as 1,2,3-triazoles.
