One Scaffold, Many Possibilities – Copper(I)‐Catalyzed Azide–Alkyne Cycloadditions, Strain‐Promoted Azide–Alkyne Cycloadditions, and Maleimide–Thiol Coupling of Ruthenium(II) Polypyridyl Complexes

Abstract

The applicability of RuII polypyridyl complexes with appropriate functionalities as substrates for biorthogonal coupling reactions is investigated. In detail, copper(I)‐catalyzed azide–alkyne cycloadditions (CuAAC), strain‐promoted azide–alkyne cycloadditions (SPAAC), and maleimide–thiol coupling reactions of ruthenium complexes are examined. The first examples of SPAAC in which the organic azide is provided by the metal complex are presented. All of the chromophores belong to one easy‐to‐synthesize scaffold, which has proven to be convenient for the application of metal chromophores. The fundamental photophysical properties of the examined compounds do not change with substitution, which is important for the design of chromophore conjugates. Furthermore, the limitations of CuAAC reactions will be discussed with regard to copper impurities in the products formed.

A Ruthenium(II) Water Oxidation Catalyst Containing a pH-Responsive Ligand Framework

“…The free ligand dppip-NO 2 was obtained via a microwave-assisted Debus−Radziszewski reaction of dppO 2 with 4-nitrobenzaldehyde and ammonium acetate in glacial acetic acid following literature-known procedures (Scheme 1). 14,15 To prevent solvation of imidazolium cations, it was crucial that the reaction mixture was neutralized with diluted ammonia (25%). This reaction resulted in a good yield of 85%, and the ligand was characterized via 1 H NMR spectroscopy (Figure S3), while 13 C NMR measurements were not possible due to low solubility.…”

“…The free ligand was synthesized according to a modified literature procedure. 15 A mixture of 154.5 mg of dppO 2 (0.42 mmol, 1 equiv), 80.9 mg of 4-nitrobenzaldehyde (0.54 mmol, 1.3 equiv), and 1.45 g of ammonium acetate (18.0 mmol, 44 equiv) was suspended in 15 mL of acetic acid. The suspension was refluxed in a microwave-assisted reaction (1.5 min 600 W, 35 min 300 W).…”

A Molecular Photosensitizer in a Porous Block Copolymer Matrix‐Implications for the Design of Photocatalytically Active Membranes

“…BlocBuilderMA was kindly donated by Sylvain Bourrigaud from Arkema (Colombes, France) and used as received. The [Ru(bpy) 2 (ipPhNH 2 )]Cl 2 photosensitizer was prepared as reported previously [18] …”

“…The [Ru(bpy) 2 (ipPhNH 2 )]Cl 2 photosensitizer was prepared as reported previously. [18] For the synthesis of the poly(styrene-co-isoprene) block the initiator Blocbuilder MA (130 mg) was dissolved in a mixture of 72.2 mL styrene ([M]/[I] = 1800) and 8.2 mL isoprene ([M]/[I] = 550). The oxygen was removed from the reaction mixture by three freezepump-thaw cycles and the reaction vessel was subsequently filled with argon.…”