A new method of synthesis of arylmalononitriles catalysed by a palladium complex

Abstract

Arylmalononitriles are prepared in good yields using a palladium-catalysed coupling reaction between aryl halides and malononitrile.

Thieno[3,2‐b]thiophene‐Diketopyrrolopyrrole‐Based Quinoidal Small Molecules: Synthesis, Characterization, Redox Behavior, and n‐Channel Organic Field‐Effect Transistors

“…The synthetic route to 3 and 4 is outlined in Scheme 2. Starting from dibromo-substituted precursors 5 and 6, the desired products 3 and 4 were synthesized through a palladium-catalyzed Takahashi coupling reaction, [31,32] followed by a modified oxidation reaction. Typical oxidation conditions for 1 and 2 with Br 2 as an oxidizing agent were initially employed, however, only low yields (< 5 %) of the target molecules were obtained, along with significant amounts of brominated byproducts that appeared to result from bromination of the quinoid thieno[3,2-b]thiophene moieties.…”

Metal‐Catalyzed α‐Arylation of Carbonyl and Related Molecules: Novel Trends in CC Bond Formation by CH Bond Functionalization

“…Motivated by their successful development of a palladium-catalyzed method to couple aryl halides with ethynyl compounds, [63] Takahashi and co-workers reported one of the first examples of intermolecular a-arylation of dicarbonyl compounds through the use of the simple first generation catalyst [PdCl 2 (PPh 3 ) 2 ] (Table 13). [64,65] Sakamoto et al [66] and Ciufolini and Browne [49] independently reported the [Pd-(PPh 3 ) 4 ]-catalyzed a-arylation of malononitriles and malonoesters in moderate yields. Ciufolini and Browne also demonstrated the intramolecular arylation of malonates.…”

Molecular and Supramolecular Architectures of Organic Semiconductors for Field‐Effect Transistor Devices and Sensors: A Synthetic Chemical Perspective

“…[93,94] Quinoidal character is conferred to these oligomers by the dicyanomethylene end-capping at both ends of the oligothiophene backbone that are introduced through the palladium-catalyzed Takahashi reaction [95] followed by oxidation. The first consequence of dicyanovinylene end-capping is a significant decrease in the band gap with respect to the corresponding α-oligothiophenes, which leads to the appearance of a biradicaloid character in the highest homologues of the series, as a consequence of the easy promotion of one electron from the HOMO to the LUMO energy level.…”