Inorganic bismuth(III) compounds can be used as low-cost and nontoxic Lewis acids. Organobismuth compounds have also been applied as reagents or catalysts in organic synthesis. However, these compounds are often air- and moisture-sensitive, which limits their practical use.

Renhua Qiu, Xinhua Xu, Shuang-Feng Yin, Hunan University, Changsha, China, and colleagues have developed an air- and water-stable Lewis-acidic organobismuth(V) compound, Ph₃Bi(OSO₂C₈F₁₇)₂ (triphenyl bismuth(V) bisperfluorooctanesulfonate). The team synthesized the compound in quantitative yield by treating Ph₃BiCl₂ with C₈F₁₇SO₂OAg in dichloromethane.

The researchers tested the compound’s catalytic activity and found high efficiency for the synthesis of nitrogen
heterocycles such as diindolylmethane derivatives, dihydropyrimidinones (pictured), dihydropyridines, and 1,2-disubstitued benzimidazoles. Additionally, the catalyst was stable and reusable. The team hopes it will find a broad range of applications in organic synthesis.

• Air-stable Organobismuth(V) Bisperfluorooctanesulfonate as an Efficient Catalyst for the Synthesis of N-Containing Compounds,
  Penghui Wang, Jinying Wang, Chak-Tong Au, Renhua Qiu, Xinhua Xu, Shuang-Feng Yina,
  Adv. Synth. Catal. 2016.
  DOI: 10.1002/adsc.201500998