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The first Zn-ProPhenol catalyzed asymmetric inverse-electron-demand Diels–Alder reaction has been accomplished. This protocol was carried out by a dual-activation mode under mild conditions, allowing the preparation of various biologically important dihydropyrans in good yields with excellent stereoselectivities. [ABSTRACT FROM AUTHOR]

A facile chiral phosphoric-acid catalyzed asymmetric inverse-electron-demand aza-Diels–Alder reaction of 1,3-diazadienes with 3-vinylindoles was established. By using this mild and practical protocol, a broad range of benzothiazolopyrimidines with three contiguous stereogenic centers were prepared in good yields and excellent diastereo- and enantio-selectivities (43 examples, up to 83% yield, >99% ee and all >20 : 1 dr). A plausible concerted reaction pathway enabled by the dual hydrogen-bonding effect was proposed to account for the observed excellent enantioselectivity and specific trans–trans diastereoselectivity. [ABSTRACT FROM AUTHOR]