TfOH-Promoted Decyanative Cyclization toward the Synthesis of 2,1-Benzisoxazoles

Abstract

A novel solvent-free, TfOH-promoted decyanative cyclization approach for the synthesis of 2,1-benzisoxazoles has been developed. The reactions are complete instantly at room temperature and result in the formation of the desired 2,1-benzisoxazoles in a 34–97% isolated yield.

Construction of a Protoberberine Alkaloid Skeleton via the Palladium-Catalyzed α-Arylation–Amide Formation Cascade

“…Previously, our group completed the synthesis of a series of nitrogen-containing heterocycles. − On this basis, we conducted preliminary studies with 1-methyl-3,4-dihydroisoquinoline and methyl 2-bromobenzoate under palladium-catalyzed conditions. Gratifyingly, we can synthesize the protoberberine derivatives in one pot.…”

Practical synthesis of 3-aryl anthranils via an electrophilic aromatic substitution strategy

“…The 3-aryl anthranil frameworks were traditionally obtained through the de novo synthesis of the isoxazole ring, 7 which suffered from limited substrate scope, toxic reagents, harsh conditions, and/or inconvenient substrates. Beyond these methods, the direct C–H arylation of simple anthranils has been established as a powerful strategy to access 3-aryl anthranils ( Fig.…”

o-Nitrophenylacetonitrile Michael additions and cyclocondensations: a novel quinoline synthesis

“…o-Nitrophenylacetonitriles, e.g., the parent 1, are valuable and versatile precursors to a variety of benzo-fused heterocycles, including indoles 2, 1-10 N-hydroxyindoles 3, [11][12][13][14][15] quinoline-N-oxides 4, [16][17][18][19][20][21] quinolines 5, [22][23][24][25][26] cinnoline-1-oxides 6, [27][28][29] and 2,1-benzisoxazoles (anthranils) 7 20,30,31 (Figure 1). As part of efforts to achieve the total synthesis of the marine pyrroloacridine natural product alpkinidine, [32][33][34] we investigated Michael addition of 1 to quinones.…”