Structural Diversity of Bismuth(III) Thiophenemonocarboxylates Isolated from Aqueous Solutions

Abstract

Five novel BiIII–thiophenemonocarboxylate (BiIII–TMC) compounds containing pyridinium cations have been synthesized from room‐temperature reactions of bismuth precursors with 2‐thiophenecarboxylic acid (HTMC) and pyridine in water. The structures have been determined by single‐crystal X‐ray diffraction, and two of the compounds have been further characterized by Raman spectroscopy and thermogravimetric analysis. The solid‐state structures of the compounds are built from anionic BiIII building units that vary in nuclearity, overall connectivity, and dimensionality. When using bismuth nitrate at a relatively low metal/ligand ratio, Hpy[Bi(TMC)4(HTMC)] (1) is formed, which consists of mononuclear units charge‐balanced by second coordination sphere pyridinium cations. With increasing metal/ligand ratios, and by consequence, increasing nitrate concentration, nitrate and carboxylate‐bridged chains of [Bi2(TMC)3(NO3)]– units in Hpy[Bi2(TMC)6(NO3)] (2), and nitrate‐bridged [Bi2(TMC)3(NO3)2]2– dimers in Hpy[Bi(TMC)3(NO3)] (3) are isolated. Starting from Bi2O3, polymorphs (Hpy)2[Bi2(TMC)8] (4) and (Hpy)2[Bi2(TMC)8] (5) are formed, both of which contain bismuth centers bridged by carboxylate groups to form dimeric units that are charge‐balanced by pyridinium cations. Presented herein is a discussion of the synthetic conditions over which 1–5 were isolated, and their solid‐state structural chemistry. The thermal stability of 1 and 3, and the spectroscopic characterization of the compounds, are also reported.

Photoluminescence of Visible and NIR‐Emitting Lanthanide‐Doped Bismuth‐Organic Materials

“…Upon heating, a gradual loss in mass is detected, likely due to removal of the partially occupied lattice water. At approximately 230 °C, a sharp drop in mass begins which is complete by 270 °C; this weight loss corresponds to decomposition of the host material to a bismuth hydroxysulfate (Bi(OH)(SO 4 )), a decomposition product which has been seen in previously reported bismuth‐thiophenecarboxylate materials . Beyond 350 °C, Bi(OH)(SO 4 ) decomposes further; the total weight loss is consistent with the formation Bi 2 O 3 which persists up to the final temperature of 600 °C.…”

Synthesis and photoluminescence of three bismuth(iii)-organic compounds bearing heterocyclic N-donor ligands

“…This results in a flexible coordination environment ranging from a hemidirected to holodirected coordination sphere, a range of coordination numbers, and thus, the potential for novel structuretypes. 14,[21][22][23][24][25][26][27] Yet, such structural diversity combined with the limited solubility and hydrolytic propensity of many Bi salt starting materials can provide significant challenges for controlled synthesis and structure prediction. As such, developing fundamental knowledge of the synthesis and structural chemistry of bismuth-organic-based phases is not only crucial for overcoming such challenges but also can provide key insight into the role that structural features have on materials properties such as luminescence.…”

Dinuclear complexes, a one dimensional chain and a two dimensional layer of bismuth(iii) chalcogenones for C–S cross coupling reactions

“…The Bi–O bond distance in 2 is (2.756(5) Å) comparable to the Bi–O distance (2.696(2)–2.718(2) Å) of Hpy[Bi 2 ( L XIII ) 6 (NO 3 )] ( L XIII = 2-thiophenecarboxylic acid). 18 The Bi····O bond length was within the van der Waals radii of Bi and O (∑ r w = r w Bi 2.05 Å + r w O 1.52 Å = 3.57 Å). 19 The distortion of octahedral coordination is also evident in the values of Cl–Bi–Cl, S–Bi–Cl, and O–Bi–Cl bond angles, which deviate significantly from the ideal values of 90° and 180°.…”