Ligand-Controlled, Palladium-Catalyzed Asymmetric [4+4] and [2+4] Cycloadditions

Qiuyu Li; Rui Pan; Meihui Wang; Hequan Yao; Aijun Lin

doi:10.1021/acs.orglett.1c00420

Ligand-Controlled, Palladium-Catalyzed Asymmetric [4+4] and [2+4] Cycloadditions

Org Lett. 2021 Mar 19;23(6):2292-2297. doi: 10.1021/acs.orglett.1c00420. Epub 2021 Mar 8.

Authors

Qiuyu Li¹, Rui Pan¹, Meihui Wang¹, Hequan Yao¹, Aijun Lin¹

Affiliation

¹ State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Bioactive Natural Product Research, Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, P. R. China.

PMID: 33683909
DOI: 10.1021/acs.orglett.1c00420

Abstract

Ligand-controlled, palladium-catalyzed asymmetric [4+4] and [2+4] cycloaddition reactions of benzofuran-derived azadienes have been developed. Taking advantage of chiral P,N-ligand (S,R_p)-PPFA, we obtained a variety of benzofuro[2,3-c][1,5] oxazocines in good yields with excellent enantioselectivities via [4+4] cycloaddition reactions. Employing chiral P,P-ligand (S)-Cl-MeO-BIPHEP, the chemo- and regioselectivities were switched to synthesize tetrahydropyran-fused spirocyclic compounds in good efficiency via [2+4] cycloaddition reactions.