Sulfoxonium-Ylide-Directed C–H Activation and Tandem (4 + 1) Annulation

Abstract

Rh(III)-catalyzed C−H activation and cyclization of sulfoxonium ylide with acrylates leads to an efficient synthesis of indanone derivatives. The reaction proceeds under mild and external metal-oxidant-free conditions. The sulfoxonium ylide acts as a traceless directing group as well as an internal oxidant. (4 + 1) Annulation after C−H activation leads to the formation of a carbocyclic ring, and the byproduct obtained is DMSO, which can be easily separated.

Metal-free synthesis of phosphinoylchroman-4-ones via a radical phosphinoylation–cyclization cascade mediated by K2S2O8

“…Notably, when the substrate was 2-allylbenzaldehyde (1j), the protocol was also compatible affording the indanone derivative 3ja with comparable yield. This outcome is of special interest, because indanone derivatives are also privileged structural motifs found in numerous natural products and pharmaceuticals with extraordinary biological and pharmaceutical activities [34,35]. However, no desired product (3ka) was obtained when there was a nitro group in the substrate (1k).…”

Metal-free synthesis of phosphinoylchroman-4-ones via phosphinoylation/cyclization cascade mediated by K2S2O8

“…Notably, when the substrate is 2-allylbenzaldehyde 1j, this protocol is also compatible affording the product 3ja as an indanone derivative. The indanone derivatives are also privileged structural motifs found in numerous natural products and pharmaceuticals with extraordinary biological and pharmaceutical activities [31,32]. However, no desired product (3ka) was obtained when there was an NO2-group in the substrate (1k).…”

Aminothiaindanone as an Accessible Scaffold for a Three-Point Chemical Diversity

“…An original one step cyclization of IX, or a two-step intramolecular Friedel-Crafts reaction led to the aminothiaindanones X. Moreover, synthetic access to this scaffold remains relevant as can be seen from recent works in carbonylation, 26 in carbocyclization, [27][28][29] direct functionalization 30,31 or in annulation of thiophene heterocycles. [32][33][34][35] Therefore, the present study has been done to explore the possible functionalization of aminothiaindanone scaffold with three diversity points: first on the thiophene ring, second on the amine group, and finally third on the ketone part of the scaffold.…”