Frontispiece: Dehalogenative or Deprotonative? The Preparation Pathway to the Organometallic Monomer for Transition‐Metal‐Catalyzed Catalyst‐Transfer‐Type Polymerization of Thiophene Derivatives

Abstract

Themis, the Goddess of Justice in the Greek mythology, judges with blindfolded eyes the case thiophene for the catalyst‐transfer‐type polymerization. The balance scale in her left hand shows the imbalance between dibromothiophene and chlorothiophene, suggesting that smaller weight loss from chlorothiophene leads to the regioregular poly(3‐substituted thiophene) in a more atom‐efficient manner. For more details see the Minireview by A. Mori and Y. Shibuya on page 6976 ff.

Nickel(II) Thiocyanate Complex as a Catalyst for Cross-Coupling Reactions

“…We have also reported that 2-halothiophenes undergo deprotonative metalation polymerization in the presence of a bulky magnesium amide, followed by the addition of a nickel(II) complex containing halides or an acetylacetonate ligand as a catalyst. 9 10 11 12 The reaction was shown to proceed in a catalyst-transfer manner, leading to highly regioregular poly(3-substituted thiophene)s when various bidentate phosphines or N-heterocyclic carbenes (NHCs) were employed as ligands. 13–15 We have also shown that a related nickel(II) catalyst can be used in the syntheses of poly-1,4-arylenes from dibromoarenes or bromo(chloro)arenes.…”