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Regioselective Crossed Aldol Reactions under Mild Conditions via Synergistic Gold-Iron Catalysis.

ABSTRACT: A synergistic gold/iron catalytic system was developed for sequential alkyne hydration and vinyl gold addition to aldehydes or ketones. Fe(acac)₃ was identified as an essential co-catalyst in preventing vinyl gold protodeauration and facilitating nucleophilic additions. Effective C-C bond formation was achieved under mild conditions (r.t.) with excellent regioselectivity and high efficiency (1% [Au], up to 95% yields). Extending reaction scope to intramolecular fashion achieved successful macrocyclization (16-31 ring sizes) with excellent yields (up to 90%, gram-scale) without extended dilution (0.2 M), which highlighted the great potential of this new crossed-aldol strategy in challenging target molecule synthesis.

SUBMITTER: Yuan T

PROVIDER: S-EPMC10798669 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Regioselective Crossed Aldol Reactions under Mild Conditions via Synergistic Gold-Iron Catalysis.

Yuan Teng T Ye Xiaohan X Zhao Pengyi P Teng Shun S Yi Yaping Y Wang Jin J Shan Chuan C Wojtas Lukasz L Jean Jonathan J Chen Hao H Shi Xiaodong X

Chem 20200410 6

A synergistic gold/iron catalytic system was developed for sequential alkyne hydration and vinyl gold addition to aldehydes or ketones. Fe(acac)<sub>3</sub> was identified as an essential co-catalyst in preventing vinyl gold protodeauration and facilitating nucleophilic additions. Effective C-C bond formation was achieved under mild conditions (r.t.) with excellent regioselectivity and high efficiency (1% [Au], up to 95% yields). Extending reaction scope to intramolecular fashion achieved succes ...[more]

PMID: 38250714

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