Bismuth(III) Triflate in Organic Synthesis

Abstract

Bismuth(III) triflate is a new, cheap and environmentally friendly Lewis acid. The research presented in this microreview is devoted to the evaluation of the scope of the uses of bismuth(III) triflate in organic synthesis.

Bi(OTf)3‐Catalyzed Diastereoselective SN1‐Type Reactions of Chiral Propargylic Acetates

“…Bi(OTf) 3 (16 mg, 10 mol %) was then added at room temperature, and the reaction mixture was stirred for 0.5 h. The reaction was quenched by the addition of a saturated solution of NaHCO 3 , and the mixture was diluted with CH 2 Cl 2 . The aqueous layer was extracted with CH 2 Cl 2 (2 20 mL) and ethyl acetate (20 mL).…”

“…[2a,b] The results led us to address the question, whether propargylic carbocations with the general structure 2 react in a similar fashion, and to investigate which parameters control their selectivity. We now report a highly diastereoselective, Bi(OTf) 3 -catalyzed [3,4] reaction of chiral propargylic acetates with various weak carbon nucleophiles, [5,6] in which chiral carbocations are very likely to be involved as intermediates. The diastereoselectivity of the reaction cannot be immediately accounted for by the preferred conformation of the cation 2.…”

“…92:8) in all cases in which product formation was observed. In the formation of 5 a, the acetate leaving group in combination with Bi(OTf) 3 as the catalyst proved to be superior to an a-chloroacetate (54 % yield) or diethylphosphate (40 % yield) group. No conversion was observed with the corresponding alcohol.…”

Single Crystal Structural Characterization of Trichlorotetrapyridylbismuth(III) and Its Pyridine Solvate

“…Unlike neighbouring heavy metals on the periodic table, bismuth exhibits low toxicity, and bismuth(III) triflate has already been used extensively as a catalyst for various organic processes. [1] The crystal structure of bismuth chloride was reported by Nyburg et al in 1971. [2] Each bismuth atom exhibited strong coordination to three chlorine atoms (2.468 -2.518 Å) in a distorted trigonal pyramidal geometry, with a further five longer interactions (3.216 -3.450 Å) to chlorine atoms which bridged to other bismuth centres.…”

Avaliação da natureza da atividade catalítica de compostos de bismuto em reações de metanólise do óleo de soja

“…Além disso, compostos de bismuto exibem acidez de Lewis de moderada a forte devido à blindagem deficiente do núcleo pelos elétrons f do átomo de bismuto (Bi = [Xe] 4f 14 , 5d 10 , 6s 2 , 6p 3 ). [18][19][20][21][22][23][24] Por consequência, o comportamento catalítico destes compostos tem sido investigado em diferentes tipos de reações químicas, exceto em reações de transesterificação, onde sua aplicação catalítica ainda é desconhecida. Por outro lado, o sólido NaBiO 3 ·2H 2 O também é frequentemente utilizado na determinação de manganês em ferro e aço.…”