Desymmetrization Of Meso-anhydrides Research Articles

Natural Product-Inspired Chiral Ligand Design: Aloperine and N-Substituted Aloperines-Induced Pd-Catalyzed Asymmetric Hydroarylation of Ketimines.

A naturally occurring alkaloid aloperine was utilized as a chiral skeleton for the development of new ligands/catalysts in asymmetric synthesis. A number of N-substituted aloperines have been prepared, and a Pd-catalyzed asymmetric hydroarylation of ketimines using these chiral 1,3-diamine ligands was reported. A range of chiral sulfonyl amides were prepared in high yields and enantioselectivities. The stereoselectivity and structure relationships of aloperines have been studied. In addition, preliminary studies on the desymmetrization of meso-anhydride have also shown that these diamines have good potential in organocatalysis. These discoveries would provide a new future development for natural product-inspired chiral ligand design and developments.

Desymmetrization of meso-Anhydrides by Dual Catalysis

Desymmetrization of meso-Anhydrides by Dual Catalysis

The first enantioselective synthesis of chiral norbornane-type 1,4-diamine ligand

The asymmetric synthesis of trans-2,3-bis(aminomethyl)norbornane was performed starting with endo-2,3-norbornene dicarboxylate anhydride. Desymmetrization of meso-anhydride 1 and following selective epimerization gave the trans-monoester (+)- 3 with a high enantiomeric excess (98% e.e.). LiAlH 4 reduction of the trans-monoester to the 1,4-diol, which was then treated with phthalimide under Mitsunobu conditions and, following a Gabriel type amine synthesis with hydrazine hydrate, yielded a saturated and unsaturated diamine mixture. Hydrogenation of mixture finally afforded saturated diamine (+)- 8 with a yield of 37%.