A new, efficient approach toward the preparation of 2-aryl-2,3-dihydrobenzofuran scaffolds through the Cu/SPDOcatalyzed [3 + 2] cycloaddition between quinone ester and styrene derivatives has been developed. The procedure features excellent enantioselectivities (up to 99% ee), high yields (up to 96%), and broad substrate tolerance. Additionally, asymmetric synthesis of natural corsifurans A and B from commercially available starting materials has also been achieved in two or three steps using this reaction as a key transformation.Letter pubs.acs.org/OrgLett

A novel and efficient approach toward the assembly of the synthetically challenging tetracyclic [6,5,7,5] core structure of calyciphylline A-type alkaloids is developed. The synthetic route features a tandem semipinacol rearrangement/Nicholas reaction that has been devised strategically to construct the spirocyclic A/B ring and the sterically congested vicinal all-carbon quaternary carbon centers in high diastereoselectivity. Late-stage installation of the hydropyrrole ring and the strained 7-membered ring via a double-reductive amination and ring-closing metathesis, respectively, has also been realized.

A novel carbon electrophile induced intermolecular oxa-Diels-Alder/semipinacol rearrangement/aldol cascade reaction of allylic silyl ether with β,γ-unsaturated α-ketoester has been developed under the promotion of SnCl4. This highly efficient transformation enables the quick construction of polycyclic architectures with up to five contiguous stereogenic centers in a single operation with moderate to good yields as well as high diastereoselectivity and would provide versatile short approaches to frameworks and/or analogues of numerous biologically important polycyclic natural products.

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Polycyclic Architectures. -A novel carbon electrophile induced intermolecular oxa-Diels-Alder/semipinacol rearrangement/aldol cascade reaction of allylic silyl ether with ,-unsaturated -ketoester is developed under the promotion of SnCl 4. This highly efficient transformation enables the quick construction of polycyclic architectures with up to five contiguous stereogenic centers in a single operation with good yields as well as high diastereoselectivity.