Gold‐Catalyzed One‐Pot A3‐Coupling/1, 5‐Hydride Shift/Schmittel‐Type Cyclization: From Aldehydes, Amines and Alkynes to the Synthesis of Benzo[b]fluorenes. Issue 9 (6th February 2020)

• Record Type: Journal Article
• Authors: Lustosa, Danilo M.; Hartmann, Deborah; Rudolph, Matthias; Rominger, Frank; Hashmi, A. Stephen K.
• Is Part Of: European journal of organic chemistry. Issue 9(2020)
• Page Start: 1160
• Page End: 1164
• Publication Date: 2020-02-06
• Subjects: Benzo[b]fluorenes -- Allenes -- Cascade reaction -- Gold -- Schmittel cyclization; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201901906
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract : A step‐economic gold‐catalyzed one‐pot synthesis of benzo[ b ]fluorenes, from aldehydes, alkynes and amines, proceeding via an A 3 ‐coupling/1, 5‐hydride shift/Schmittel‐type cyclization is described. The formation of the allene intermediate is not dependent on a previous installation of reaction triggers, and upon cyclization delivered benzo[ b ]fluorenes. With this method, just by an easy modification of the starting materials in a modular way, nineteen benzo[ b ]fluorenes, bearing different substituents Ar 1, Ar 2 and Ar 3, were prepared. Overall, three new carbon–carbon bonds are formed in one‐pot. Abstract : A short cut to anellated systems by gold catalysis is based on a combination of a gold‐catalyzed A 3 ‐coupling followed by a 1, 5‐hydride shift and a Schmittel‐type cyclization in a single synthetic operation.