Opening the paddlewheel: unusual coordination of [Mo2] dumbbells in the chain structures of A[Mo2(CF3SO3)5]·2CF3SO3H (A = Na, Rb, Cs)

Abstract

The reaction of Mo(II)acetate, concentrated triflic acid and the alkaline metal triflates A(CF(3)SO(3)) (A = Na, Rb, Cs) in sealed glass ampoules at 110 °C yielded red single crystals of A[Mo(2)(CF(3)SO(3))(5)]·2CF(3)SO(3)H (A = Na: triclinic, P-1, Z = 4, a = 13.714(1) Å, b = 14.339(1) Å, c = 21.340(2) Å, α = 81.78(1)°, β = 75.21(1)°, γ = 62.65(1)°; A = Rb/Cs: monoclinic, P2(1)/m, Z = 2, a = 11.561(1)/11.584(1) Å, b = 14.817(1)/14.9472(8) Å, c = 11.6208(1)/11.744(1) Å, β = 112.38(1)/113.48(1)°). The crystal structures contain dumbbell shaped [Mo(2)] moieties surrounded by three chelating and four monodentate triflate anions leading to an opening of the typical paddlewheel fragment at one of its edges. The monodentate triflate anions are connected to further [Mo(2)] dumbbells leading to infinite anionic chains according to (∞)(1)[Mo(2)(CF(3)SO(3))(3/1)(CF(3)SO(3))(4/2)](-). The charge balance is achieved by the alkaline metal ions that are additionally coordinated by triflic acid molecules. Theoretical investigations were preformed on the open paddlewheel fragment and are in good agreement with the experimental findings. According to DTA/TG measurements and the XRD investigations the decomposition of the compounds occurs in multiple steps and leads to MoO(2) and A(2)MoO(4).

A Highly Triflated Rare‐Earth Ion in [Eu(O3SCF3)8]5−

“…[10] Moreover, the metal-metal bonded-molybdenum compounds M[Mo 2 (O 3 SCF 3 ) 5 ]·2 CF 3 SO 3 H( M = Na, Rb, Cs) have been prepared when molybdenum(II) acetate was used as starting material. [11] Nevertheless, it mustb es tated that also triflic acid is ap roblematic mediumf or crystallization. In the majority of reactions, we were not able to obtain crystalline or even single crystalline material.…”

Water‐Stable Zirconium‐Based Metal–Organic Framework Material with High‐Surface Area and Gas‐Storage Capacities

“…We have also used triflic acid successfully in these reactions, and obtained, for example, the aurates M[Au(OTf) 4 ] (M=Li–Rb, Ag) and the thallium triflate KTl(OTf) 4 with octahedral Tl 3+ coordination 10. Moreover, the metal–metal bonded‐molybdenum compounds M[Mo 2 (O 3 SCF 3 ) 5 ]⋅2 CF 3 SO 3 H (M=Na, Rb, Cs) have been prepared when molybdenum(II) acetate was used as starting material 11. Nevertheless, it must be stated that also triflic acid is a problematic medium for crystallization.…”

Trichlates, an Unattended Class of Compounds: Characterization of Cl3CSO2Cl, and (H5O2)[Cl3CSO3]

“…[8] We became interested in trichloromethanesulfonic acid in course of our investigations of sulfuric acid derivatives, particularly of trifluoromethanesulfonates. [9][10][11] It turned out that the limited knowledge of trichlates is scarce because the synthesis of the related acid is quite tedious and hazardous. However, the starting materials for the preparation of trichloromethanesulfonic acid, CS 2 and Cl 2 , are readily available and relatively cheap chemicals.…”