Ruthenium-Catalyzed C–H Activation of Salicylaldehyde and Decarboxylative Coupling of Alkynoic Acids for the Selective Synthesis of Homoisoflavonoids and Flavones
作者:Gabriel Charles Edwin Raja、Ji Yeon Ryu、Junseong Lee、Sunwoo Lee
DOI:10.1021/acs.orglett.7b03325
日期:2017.12.15
Homoisoflavonoids were formed in DMSO exclusively, and flavones were formed in t-AmOH when salicylaldehyde and alkynoicacids reacted with [Ru(p-cymene)Cl2]2 and CsOAc. They were formed through C–H activation of salicylaldehyde and decarboxylative coupling of alkynoicacid. This reaction system showed good yields, broad substrate scope, and good functional group tolerance. It was found that chalcone
Palladium-Catalyzed Cross-Coupling of Alkynyl Carboxylic Acids with Isocyanides: Solvent-Controlled Selective Synthesis of 5-Iminofuranones and 5-Iminopyrrolones
A novel palladium‐catalyzed cyclization of alkynyl carboxylic acids with isocyanides has been successfully developed herein. The corresponding 5‐iminofuranone or 5‐iminopyrrolone derivatives were constructed in moderate to good yields which were well controlled by the solvents. These reactions proceed under simple and mild reaction conditions with high efficiency, and feature a wide substrate scope
Nickel-Catalyzed Hiyama-type Decarboxylative Coupling of Propiolic Acids and Organosilanes
作者:Gabriel Charles Edwin Raja、Francis Mariaraj Irudayanathan、Han-Sung Kim、Jimin Kim、Sunwoo Lee
DOI:10.1021/acs.joc.6b00883
日期:2016.6.17
the decarboxylative coupling reaction of alkynyl carboxylic acids with organosilanes. Ni(acac)2 and 1,10-phenanthroline showed the best result in the presence of CsF and CuF2 at 120 °C. This system tolerated the presence of alkyl, alkoxy, halogen, nitro, cyano, ketone, and ester functional groups. Moreover, the reaction with but-2-ynedioic acid and organosilane afforded the corresponding symmetrical diarylalkynes
Enantioselective Decarboxylative α-Alkynylation of β-Ketocarbonyls via a Catalytic α-Imino Radical Intermediate
作者:Dehong Wang、Long Zhang、Sanzhong Luo
DOI:10.1021/acs.orglett.7b02386
日期:2017.9.15
A distinctive aminocatalysis via α-imino radical is reported on the basis of SET oxidation of a secondary enamine. The combination of chiral primary amine catalysis and visible-light photoredox catalysis enables the enantioselective decarboxylativecoupling of propiolicacid and β-ketocarbonyls to afford alkynylation adducts with high enantioselectivity. Mechanism studies indicate the reaction proceeds