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Fluorohydration of alkynes via I(I)/I(III) catalysis.

ABSTRACT: Substrate specificity is ubiquitous in biological catalysis, but less pervasive in the realm of small-molecule catalysis. Herein, we disclose an intriguing example of substrate specificity that was observed whilst exploring catalysis-based routes to generate ?-fluoroketones from terminal and internal alkynes under the auspices of I(I)/I(III) catalysis. Utilising p-TolI as an inexpensive organocatalyst with Selectfluor^® and amine/HF mixtures, the formation of protected ?-fluoroketones from simple alkynes was realised. Whilst the transient p-TolIF₂ species generated in situ productively engaged with pentynyl benzoate scaffolds to generate the desired ?-fluoroketone motif, augmentation or contraction of the linker suppressed catalysis. The prerequisite for this substructure was established by molecular editing and was complemented with a physical organic investigation of possible determinants.

SUBMITTER: Neufeld J

PROVIDER: S-EPMC7356369 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Fluorohydration of alkynes via I(I)/I(III) catalysis.

Neufeld Jessica J Daniliuc Constantin G CG Gilmour Ryan R

Beilstein journal of organic chemistry 20200710

Substrate specificity is ubiquitous in biological catalysis, but less pervasive in the realm of small-molecule catalysis. Herein, we disclose an intriguing example of substrate specificity that was observed whilst exploring catalysis-based routes to generate α-fluoroketones from terminal and internal alkynes under the auspices of I(I)/I(III) catalysis. Utilising <i>p</i>-TolI as an inexpensive organocatalyst with Selectfluor<sup>®</sup> and amine/HF mixtures, the formation of protected α-fluorok ...[more]

PMID: 32704329

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