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Asymmetric higher-order [10 + n] cycloadditions of palladium-containing 10π-cycloaddends.

ABSTRACT: We uncovered an asymmetric higher-order [10 + 2] cycloaddition reaction between diverse activated alkenes and a new type of π-allylpalladium complex-containing dipole-type 10π-cycloaddend, which was generated in situ from 2-methylene-1-indanols via a dehydrative insertion and deprotonation strategy under double activation of Pd(0) and phosphoric acid. A similar strategy was applied to an asymmetric higher-order [10 + 8] cycloaddition reaction or [10 + 4] cycloaddition reaction by using a heptafulvene derivative or a cyclic enone, respectively, as the acceptor. A variety of polycyclic frameworks imbedding an indene core were generally furnished in moderate to excellent yields with high levels of enantioselectivity by employing a newly designed chiral phosphoramidite ligand.

SUBMITTER: Li A

PROVIDER: S-EPMC9384823 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Asymmetric higher-order [10 + n] cycloadditions of palladium-containing 10π-cycloaddends.

Li Ao A Gao Yang Y Lu Jian-Bin JB Chen Zhi-Chao ZC Du Wei W Chen Ying-Chun YC

Chemical science 20220715 32

We uncovered an asymmetric higher-order [10 + 2] cycloaddition reaction between diverse activated alkenes and a new type of π-allylpalladium complex-containing dipole-type 10π-cycloaddend, which was generated in situ from 2-methylene-1-indanols via a dehydrative insertion and deprotonation strategy under double activation of Pd(0) and phosphoric acid. A similar strategy was applied to an asymmetric higher-order [10 + 8] cycloaddition reaction or [10 + 4] cycloaddition reaction by u ...[more]

PMID: 36092999

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