A Lewis base-Brønsted acid co-catalyzed Morita-Baylis-Hillman reaction of cyclic sulfamidate imines with acrylate-type Michael acceptors has been developed. The combination of equimolecular catalytic amounts of DABCO and acetic acid proved highly efficient and tolerated well a wide range of Michael acceptors and substituted 6-membered ring sulfamidate imines, as well as a sultam derivative. The reaction provides a straightforward access to sulfamidates bearing α,β-unsaturated chains, which allows for the further functionalization of the products. Moreover, the robustness and applicability of the method was demonstrated by performing a gram scale reaction and further functionalization of the MBH-adducts.

The use of (benzo)pyrylium salts as versatile synthetic building blocks has become an attractive platform for the preparation of valuable heterocyclic compounds. Besides other numerous direct applications of (benzo)pyryliums, the intrinsic electrophilic nature of these species or the dipole character of the related oxidopyrylium derivatives have been exploited towards the development of enantioselective transformations such as nucleophilic dearomatization and cycloaddition reactions. This review aims at providing an overview on the relevant catalytic enantioselective methodologies developed in the past years, which are presented considering the involved metal- and/or organic catalytic system, as well as the type of reaction.