Rh-Catalyzed aminative dearomatization of 2-naphthols.

A direct aminative dearomatization of 2-naphthols was achieved. In the presence of 1 mol% Rh2(esp)2 and 3 equivalents of O-(2,4-dinitrophenyl)hydroxylamine (DPH) as readily available aminating reagents, the reactions of 2-naphthols afforded unprotected α-amino-ß-naphthalenones in good yields under mild reaction conditions. The conditions were compatible with gram-scale reaction, and the product could undergo diverse transformations.

Copper(I)-Catalyzed Asymmetric Dearomatization of Indole Acetamides with 3-Indolylphenyliodonium Salts.

The rapid and direct asymmetric synthesis of 3-(3a-indolyl)hexahydropyrroloindoline motifs is an extremely important part of the total synthesis of several alkaloid structures. Herein, an intermolecular, asymmetric cascade dearomatization reaction of indole acetamides with 3-indolylphenyliodonium salts has been developed. This protocol provides a straightforward access to 3-(3a-indolyl)hexahydropyrroloindolines bearing an all-carbon quaternary stereocenter at the C3 position of the indoline ring with high enantioselectivities. The utility of the protocol has been demonstrated by the formal asymmetric synthesis of folicanthine.

Enantioselective Synthesis of 3a-Amino-Pyrroloindolines by Copper-Catalyzed Direct Asymmetric Dearomative Amination of Tryptamines.

A direct asymmetric dearomative amination of tryptamines with O-(2,4-dinitrophenyl)hydroxylamine (DPH) was achieved using CuBr-bisoxazoline complex as a catalyst, affording 3a-amino-pyrroloindolines in good to excellent enantioselectivity under mild reaction conditions. Furthermore, the synthetic value of this method was demonstrated in the total synthesis of (-)-psychotriasine in a highly concise manner.

Synthesis of C3-Methyl-Substituted Pyrroloindolines and Furoindolines via Cascade Dearomatization of Indole Derivatives with Methyl Iodide.

A highly efficient method for constructing C3-methyl-substituted pyrroloindolines and furoindolines via cascade dearomatization reaction of indole derivatives with methyl iodide was developed. This protocol offers a direct approach to a wide range of C3 methyl substituted pyrroloindolines under mild conditions. The utility of this method was further demonstrated in the concise synthesis of (±)-esermethol.