A Caltech Library Service

Expanding the Chiral Monoterpene Pool: Enantioselective Diels–Alder Reactions of α-Acyloxy Enones

Mendoza, Skyler D. and Rombola, Michael and Tao, Yujia and Zuend, Stephan J. and Götz, Roland and McLaughlin, Martin J. and Reisman, Sarah E. (2022) Expanding the Chiral Monoterpene Pool: Enantioselective Diels–Alder Reactions of α-Acyloxy Enones. Organic Letters, 24 (21). pp. 3802-3806. ISSN 1523-7060. doi:10.1021/acs.orglett.2c01343.

[img] PDF (Detailed experimental procedures, compound characterization data, and ¹H, ¹³C, and ¹⁹F NMR spectra) - Supplemental Material
See Usage Policy.


Use this Persistent URL to link to this item:


An enantioselective Diels–Alder (DA) reaction of α-acyloxy enones has been developed to synthesize chiral oxidized cyclohexenes. Yttrium(III) triflate, in conjunction with a chiral pyridinebisimidazoline (PyBim) ligand, was found to catalyze the asymmetric [4 + 2] cycloaddition with a variety of dienes and α-acyloxy enone dienophiles. Using this method, terpinene-4-ol, a key intermediate in the synthesis of commercial herbicide cinmethylin, can be prepared in four steps from isoprene. A combination of kinetic data and NMR studies support a mechanism involving reversible binding of a dienophile to a yttrium catalyst followed by cycloaddition with a diene as the rate-determining step.

Item Type:Article
Related URLs:
URLURL TypeDescription
Mendoza, Skyler D.0000-0003-1939-1884
Rombola, Michael0000-0002-4402-5619
Tao, Yujia0000-0003-4615-6409
Zuend, Stephan J.0000-0002-4420-000X
Reisman, Sarah E.0000-0001-8244-9300
Additional Information:© 2022 American Chemical Society. Received 17 April 2022. Published online 20 May 2022. This work was financially supported by BASF (SA-9852). We thank Dr. S. Virgil (Caltech) and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. Nicholas J. Fastuca (Caltech) is gratefully acknowledged for experimental help regarding kinetics experiments. Dr. Caitlin R. Lacker (Caltech) is gratefully acknowledged for discussion of the substrate scope. Author Contributions. S.D.M. and M.R. contributed equally. The authors declare the following competing financial interest(s): A patent has been filed: Reisman, S.; Rombola, M.; Ladd, C. L.; McLaughlin, M. J.; Zuend, S.; Götz, R. Process for the synthesis of non-racemic cyclohexenes. US Patent WO 2021/007141 A1, January 2021.
Funding AgencyGrant Number
BASF CorporationSA-9852
Subject Keywords:Addition reactions, Catalysts, Cyclization, Ligands, Organic compounds
Issue or Number:21
Record Number:CaltechAUTHORS:20220523-165225000
Persistent URL:
Official Citation:Expanding the Chiral Monoterpene Pool: Enantioselective Diels–Alder Reactions of α-Acyloxy Enones. Skyler D. Mendoza, Michael Rombola, Yujia Tao, Stephan J. Zuend, Roland Götz, Martin J. McLaughlin, and Sarah E. Reisman. Organic Letters 2022 24 (21), 3802-3806; DOI: 10.1021/acs.orglett.2c01343
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:114886
Deposited By: George Porter
Deposited On:23 May 2022 20:03
Last Modified:16 Jun 2022 17:57

Repository Staff Only: item control page