Asymmetric Diels–Alder reaction of chalcone and isoprene mediated by titanium-based complexes

Abstract

The asymmetric Diels–Alder reaction of chalcone and isoprene has been accomplished by use of chiral titanium complexes. Notably, an enantiomeric excess as high as 61% and a regioselectivity of 95% have been achieved. The preparation of the chiral titanium complexes is simple and does not require the pre-installation of a chiral auxiliary. This study represents the first example of asymmetric Diels–Alder reaction between chalcone and isoprene.

Graphical Abstract

Keywords:

• [4 + 2] cycloaddition
• enantiomeric synthesis
• 2-methyl-1,3-butadiene
• trans-chalcone
• titanium tetrachloride

Acknowledgment

This work was supported by Universiti Malaya Research Grants (IIRG003B-2019 and BK044-2017).

Disclosure statement

The authors confirm that they have no conflict of interest with respect to the work described in this manuscript.

Additional information

Funding

This work was supported by Universiti Malaya Research Grants (IIRG003B-2019 and BK044-2017).