Advances in Organocatalytic 1,6-Addition Reactions: Enantioselective Construction of Remote Stereogenic Centers

Due to the competing 1,4-addition reactions and the distance from the chirality information, the construction of a remote stereogenic center via 1,6-addition reactions is often regarded as a great challenge in asymmetric synthesis. Recently, the use of organocatalysts has provided new, excellent alternatives to activate the remote delta-position and facilitate the enantioselective 1,6-addition reactions. In this regard, different new activation modes have been devised and new types of substrates have been employed. This review describes all the recent developments in this area.