Formylation of aromatic compounds with carbon monoxide in HSO3F-SbF5 uner atmospheric pressure

A New Rhodium Catalyst: Formation of [Rh(CO)4]+ in Concentrated Sulfuric Acid and Its Application to Carbonylation of Olefins

“…Strong acids and superacids have been used as useful reaction media and catalysts in organic syntheses and industrial processes, including the cationic carbonylation of methane and its substituted derivatives and the formylation of aromatic compounds . In concd H 2 SO 4 , the olefin is protonated to form a carbocation intermediate, which isomerizes to a tert -carbocation via the Wagner-Meerwein rearrangement .…”

Superacid‐Catalyzed Reactions

“…Studying the formylation of alkylbenzenes in HSO 3 F-SbF 5 , Tanaka et al 436 have observed both formylation and sulfonation. However, in the presence of HSO 3 F, that is at low acidity level, only sulfonyl compounds were obtained [Eq.…”

Selective and Efficient Formylation of Indoles (C3) and Pyrroles (C2) Using 2,4,6‐Trichloro‐1,3,5‐Triazine/Dimethylformamide (TCT/DMF) Mixed Reagent

“…Moreover, during the multistep synthesis of many natural products, formylation reaction is often necessary, and the selectivity, simplicity, and efficiency of this step are highly critical . Some of the widely used formylating agents that have been reported up to now are POCl 3 / N , N ‐dimethylformamide (DMF) , HCO 2 H/ N,N′ ‐Dicyclohexylcarbodiimide (DCC) , 2,2,2‐trifluoroethyl formate , formic acid/1‐Ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide (EDAC) , acetic formic anhydride , formyl‐pivaloyl anhydride , cyanomethylformate , pentafluorophenyl formate , imidazole/DMF , MeOH/Ru , CO 2 /PhMe 2 SiH , AgOTf/Cl 2 CHOMe , tetramethylethylenediamine/O 2 /visible light , FeCl 3 /DMSO , CO/acid , 2‐benzotriazolyl‐1,3‐dioxolane , N ‐methyl aniline/Ru , Pd/CO/H 2 , tert ‐butyl isocyanide , Pd/CH 3 NO 2 , etc. In spite of the diversity of formylating agents, there are serious restrictions for the preparation of some of them, such as harsh experimental conditions, the use of unusual reagents, formation of unwanted or toxic byproducts, use of expensive procedures for their synthesis, and thermal instability of the reagents.…”