Carbon Nucleophile-Initiated Rauhut-Currier Reaction: An Atom-Economical Synthesis of Highly Functionalized Carbocycles

Cs2CO3-Catalyzed Rauhut-Currier-Type Reaction for the Synthesis of 2,3-Dihydrobenzo[b]oxepin Derivatives

The synthesis of fused benzoxepines relies on the use of complex substrates and methodologies. Herein, we report our experimental and theoretical findings about an unprecedented Rauhut-Currier-type reaction catalyzed by Cs2CO3 to access these important compounds. The developed methodology avoids the use of phosphine- or amine-based catalysts and additives. The reaction can be performed under microwave irradiation and proceeds with complete chemoselectivity.

Phosphine-promoted intramolecular Rauhut-Currier/Wittig reaction cascade to access (hetero)arene-fused diquinanes

We describe the first phosphine-promoted intramolecular Rauhut-Currier reaction that triggers an intramolecular Wittig process assembling new classes of diquinanes. The one-pot strategy provides ready access to simple diquinanes and various (hetero)arene-fused diquinanes incorporated with up to two contiguous all-carbon quaternary centers under metal-free and neutral conditions. We showcased the generality of the method on a broad range of substrates and demonstrated its synthetic utility in accessing various advanced intermediates relevant to natural product synthesis and material science.

Non-covalent interactions in the diastereoselective synthesis of cis-2,3-dihydrobenzofurans: experimental and computational studies

The diastereoselective synthesis of 2,3-DHBs has been previously reported via an intramolecular Michael addition reaction using alkali bases such as Cs2CO3 and K2CO3. However, no systematic study has been performed to understand the possible role of bases in the mechanism of the reaction and factors behind the stereoselective outcome of the reaction. Herein, from experimental and theoretical points of view, we disclose the role of the cesium salt in the rate-determining step along the catalytic cycle and the key role of stabilizing non-covalent interactions in the stereoselective outcome of the reaction.