Chemo‐selective copper‐catalyzed C‐O coupling reactions of phenols with aryl/vinyl halides using enaminone as efficient ligand

Abstract

The copper-catalyzed Ullmann C-O coupling reactions between phenols and aryl/vinyl halides have been efficiently performed by employing (E)-3-(dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-one, an easily available enaminone, as ligand. This new ligand is advantageous for its easy availability, broad applicability and good efficiency. a Reaction conditions: 1 mmol phenol 2, 1 mmol vinyl bromides 5, 10 mol % CuI and 20 mol% L, 2 mmol Cs 2 CO 3 in 1.5 ml DMSO, 130 C, 24 h. b Isolated yield. Copper-catalyzed O-arylationAppl.

Picolinamides as Effective Ligands for Copper‐Catalysed Aryl Ether Formation: Structure–Activity Relationships, Substrate Scope and Mechanistic Investigations

“…In the case of 8‐hydroxyquinoline, taking into account the stabilisation of its Cu II complexes (see below), the failure of the coupling is not entirely surprising, [56] although this substrate can react at higher temperature or by using microwave techniques 56. 60, 61 In 8‐hydroxyquinaldine, the methyl group might act as a destabilising agent for its copper complex, thus making the substrate more available for the coupling. Due to their ligating ability, these substrates would probably require different reaction conditions to react properly.…”

Disulfides as efficient thiolating reagents enabling selective bis-sulfenylation of aryl dihalides under mild copper-catalyzed conditions

“…Following our previous work on copper-catalyzed selective mono-sulfenylation (Scheme 1) 32 as well as other related coppercatalyzed coupling chemistry, [33][34][35][36][37] we report herein the coppercatalyzed selective bis-sulfenylation of dihaloaryls under mild and clean conditions by using disuldes as bis-thiolating agents 38 (Scheme 1).…”

Synthesis of heteroaryl containing sulfides via enaminone ligand assisted, copper-catalyzed C–S coupling reactions of heteroaryl thiols and aryl halides

“…26 On the basis of this interesting transformation, we have recently conducted extensive investigation on enaminonebased ligand assisted Ullmann C-heteroatom and C-C coupling reactions in order to expand the application scope of this kind of ligands for the synthesis of structurally diverse organic products. [27][28][29][30] Based on the structure of products 3, the C-H hydroxylation may possibly happen in either the aryl backbone in the thiophenols or the halides. While the examples using aryl and heteroaryl halides both provide hydroxylated suldes 3 in the previous work, however, the reactions using heteroaryl thiols 4 have not been examined.…”