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Uncovering Subtle Ligand Effects of Phosphines Using Gold(I) Catalysis.

ABSTRACT: Herein, we report the integration of simple linear regressions with gold(I) catalysis to interrogate the influence of phosphine structure on metal-catalyzed organic transformations. We demonstrate that observed product ratios in [4 + 3]/[4 + 2] cycloisomerization processes are influenced by both steric and electronic properties of the phosphine, which can be represented by the Au-Cl distance. In contrast, the observed selectivity of a similar [2 + 3]/[2 + 2] cycloisomerization is governed by L/B1, a steric parameter. Using this correlation, we were able to accurately predict the selectivity of a previously untested, Buchwald-type ligand to enhance selectivity for the same transformation. This ligand found further utility in increasing the selectivity of a previously reported gold-catalyzed cycloisomerization/arylation of 1,6-enynes by ~1 kcal/mol.

SUBMITTER: Christian AH

PROVIDER: S-EPMC5909821 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Uncovering Subtle Ligand Effects of Phosphines Using Gold(I) Catalysis.

Christian Alec H AH Niemeyer Zachary L ZL Sigman Matthew S MS Toste F Dean FD

ACS catalysis 20170510 6

Herein, we report the integration of simple linear regressions with gold(I) catalysis to interrogate the influence of phosphine structure on metal-catalyzed organic transformations. We demonstrate that observed product ratios in [4 + 3]/[4 + 2] cycloisomerization processes are influenced by both steric and electronic properties of the phosphine, which can be represented by the Au-Cl distance. In contrast, the observed selectivity of a similar [2 + 3]/[2 + 2] cycloisomerization is governed by L/B ...[more]

PMID: 29686935

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