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Iridium-Catalyzed Asymmetric Ring-Opening of Oxabenzonorbornadienes with N-Substituted Piperazine Nucleophiles.

ABSTRACT: Iridium-catalyzed asymmetric ring-opening of oxabenzonorbornadienes with N-substituted piperazines was described. The reaction afforded the corresponding ring-opening products in high yields and moderate enantioselectivities in the presence of 2.5 mol % [Ir(COD)Cl]? and 5.0 mol % (S)-p-Tol-BINAP. The effects of various chiral bidentate ligands, catalyst loading, solvent, and temperature on the yield and enantioselectivity were also investigated. A plausible mechanism was proposed to account for the formation of the corresponding trans-ring opened products based on the X-ray structure of product 2i.

SUBMITTER: Yang W

PROVIDER: S-EPMC6332042 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Iridium-Catalyzed Asymmetric Ring-Opening of Oxabenzonorbornadienes with N-Substituted Piperazine Nucleophiles.

Yang Wen W Luo Renshi R Yang Dingqiao D

Molecules (Basel, Switzerland) 20151127 12

Iridium-catalyzed asymmetric ring-opening of oxabenzonorbornadienes with N-substituted piperazines was described. The reaction afforded the corresponding ring-opening products in high yields and moderate enantioselectivities in the presence of 2.5 mol % [Ir(COD)Cl]₂ and 5.0 mol % (S)-p-Tol-BINAP. The effects of various chiral bidentate ligands, catalyst loading, solvent, and temperature on the yield and enantioselectivity were also investigated. A plausible mechanism was proposed to account for ...[more]

PMID: 26633315

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