Six-Membered N-Heterocyclic Carbine-Based Catalysts for Asymmetric Reactions

The present invention relates to the field of asymmetrical catalysts used for transition formations in a wide variety of organic synthesis reactions.

The catalyst is a N-heterocyclic carbine (NHC) having three fused rings with first and second rings being six-membered rings and the third being a five-membered ring. The first ring is fused to the second and has four substituents. The second ring has two nitrogens flanking a carbine atom with one nitrogen bound to a substituent. The carbene atom may optionally be bonded to a metal. The third ring is fused to the second ring and contains two nitrogens. The third ring of the catalyst has a double bond and two substituents on adjacent non-fused carbons. A non-fused nitrogen of the third ring is partially bonded to another substituent. Methods for the synthesis and use of the catalyst embodiments of the present invention are also provided.

The new 6-NHC ligand and ligand-metal catalyst discovered and designed in this invention are relatively easy to prepare and shows excellent activity and enantioselectivity, for use in a variety of organic reactions.