Palladium-catalyzed phosphine-, copper-free and aerobic Sonogashira coupling in aqueous media

Abstract

A simple, highly efficient and phosphine-free protocol for the Sonogashira coupling of aryl iodides with terminal alkynes has been developed using Pd 2 (dba) 3 (dba=dibenzylideneacetone) as the catalyst under aqueous, copper-free and aerobic conditions. The coupling of aryl iodides with aromatic terminal alkynes provided good to excellent yields and moderate to good yields were achieved using aliphatic terminal alkynes as one of the coupling partners. Aqueous ethanol as solvent is economical and environmentally benign in accordance with the concept of green chemistry.

Effect of Substrates on Catalytic Activity of Biogenic Palladium Nanoparticles in C–C Cross-Coupling Reactions

“…Method A provides efficient cross-coupling for diverse range of substrates (Table , 6d–6u). It is compatible for aliphatic alkynes which in general is low reactive in nature (Table , 6q–6u). , Aryl iodides-bearing electron withdrawing groups in p- and m-positions proceed to completion of reaction with excellent yield of the cross-coupling product (Table , 6d, 6f, 6g, 6l–p). However, electron-donating aryl iodides are less competent in comparison to the later (Table , entry 6h & 6i).…”

Solvent‐Free Synthesis of Core‐Functionalised Naphthalene Diimides by Using a Vibratory Ball Mill: Suzuki, Sonogashira and Buchwald–Hartwig Reactions

“…Notwithstanding, diacetylene‐substituted c‐NDIs have suitable electronic properties for use in OLEDs [27c,36] and n‐type semiconductor materials [37] amongst other applications [38] . Typical Sonogashira reaction conditions include the use of either an organic base such as diazabicyclooctane (DABCO) [13a] or an inorganic base such as K 3 PO 4 , [39] and a palladium source [40] . All reported solution‐state Sonogashira coupling reactions to form c‐NDIs require the addition of a copper co‐catalyst [27a,c,41] .…”

Chroman‐4‐one‐Based Amino Bidentate Ligand: An Efficient Ligand for Suzuki‐Miyaura and Mizoroki‐Heck Coupling Reactions in Aqueous Medium

“…Screening of other solvent also reveals that solvent other than water gave lower yield of the product 10 a (Table 3, entries [11][12][13][14][15][16][17][18][19][20]. Moreover the use of other palladium salt like Pd(OAc) 2 and Pd(OTf) 2 remarkably decreased the yield of product 10 a yield (Table 3, entries 21,22).…”

“…These ligands are thermally stable, and are well-known for their great tenability by varying substituents on the donor atoms, and they can be bind to central metal atom in either the ionic state or neutral state. [19][20][21] Due to the high stability and high bind affinity of N-, O-based ligand with transition metal and their use in coupling reaction is still demand in synthetic chemistry. Despite this, few chromenebased ligands or complexes with N, and O donor atom are reported in literature, and noticed that these ligands or complexes was very good for Suzuki and heck coupling reaction.…”