Synthesis and Characterization of Eu(BPDS) (BPDS = 4, 4′‐biphenyldisulfonate), a Solvent‐Free Sulfonate of Divalent Europium

Eu(BPDS) (BPDS = 4, 4 ′ ‐biphenyldisulfonate) has been obtained as a yellow powder from the metathesis reaction of Eu(CF 3 SO 3 ) 2 (CH 3 CN) and either [PPh 4 ] 2 BPDS (Ph = phenyl, C 6 H 5 ) or [PNP] 2 BPDS (PNP = bis (triphenylphosphine)‐iminium) in CH 3 CN. The monoclinic structure of EuBPDS ( P 2 1 / n , Z = 4, a = 6.27(1) Å, b = 28.91(8) Å, c = 7.32(2) Å, β = 95.0(2)°) is determined by X‐ray powder diffraction based on single crystal data of the isotypic strontium compound ( P 2 1 / n , Z = 4, a = 6.0449(7) Å, b = 28.831(3) Å, c = 7.2393(8) Å, β = 97.226(4)°), which is prepared from SrCO 3 and H 2 BPDS in an aqueous solution. In both structures, the M 2+ ions (M = Eu, Sr) are sevenfold coordinated by oxygen atoms. The sulfonate groups of the BPDS 2– anion connect the metal centers in the (010) plane of the monoclinic unit cell, while the biphenyl moieties align along the [010] direction. The infrared spectra of both compounds are nearly identical, confirming their isotypic nature. The second product of the metathesis reactions is the triflate [PPh 4 ](CF 3 SO 3 ), the triflates [PNP](CF 3 SO 3 )‐I, [PNP](CF 3 SO 3 )‐II, and [PNP](CF 3 SO 3 )(DME), which are also structurally characterized.