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Organocatalyzed Visible Light-Mediated gem-Borosilylcyclopropanation.

ABSTRACT: The borosilylcyclopropanation of styrene derivatives using a (diiodo(trimethylsilyl)methyl)boronic ester carbene precursor is reported herein. The key reagent was synthesized in a 4-step sequence using inexpensive and commercially available starting materials. This method enabled the preparation of novel 1,1,2-tri- and 1,1,2,2-tetrasubstituted borosilylcyclopropanes up to excellent yields and diastereoselectivity. The reaction is organocatalyzed by eosin Y in the presence of visible light. A mechanism consistent with the experimental observations was postulated based on density functional theory calculations. The versatility of these entities was highlighted through post-functionalization reactions.

SUBMITTER: Thai-Savard L

PROVIDER: S-EPMC10106276 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Organocatalyzed Visible Light-Mediated <i>gem</i>-Borosilylcyclopropanation.

Thai-Savard Léa L Sayes Morgane M Perreault-Dufour Josiane J Hong Gang G Wells Lucille A LA Kozlowski Marisa C MC Charette André B AB

The Journal of organic chemistry 20230119 3

The borosilylcyclopropanation of styrene derivatives using a (diiodo(trimethylsilyl)methyl)boronic ester carbene precursor is reported herein. The key reagent was synthesized in a 4-step sequence using inexpensive and commercially available starting materials. This method enabled the preparation of novel 1,1,2-tri- and 1,1,2,2-tetrasubstituted borosilylcyclopropanes up to excellent yields and diastereoselectivity. The reaction is organocatalyzed by eosin Y in the presence of visible light. A mec ...[more]

PMID: 36655845

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