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Thiophosphonium-Alkyne Cycloaddition Reactions: A Heavy Congener of the Carbonyl-Alkyne Metathesis.

ABSTRACT: While the metathesis reaction between alkynes and thiocarbonyl compounds has been thoroughly studied, the reactivity of alkynes with isoelectronic main group R₂E=S compounds is rarely reported and unknown for [R₂P=S]⁺ analogues. We show that thiophosphonium ions, which are the isoelectronic phosphorus congeners to thiocarbonyl compounds, undergo [2 + 2]-cycloaddition reactions with different alkynes to generate 1,2-thiaphosphete ions. The four-membered ring species are in an equilibrium state with the corresponding P=C-C=S heterodiene structure and thus undergo hetero-Diels-Alder reactions with acetonitrile. Heteroatom and substituent effects on the energy profile of the 1,2-thiaphosphete formation were elucidated by means of quantum chemical methods.

SUBMITTER: Lowe P

PROVIDER: S-EPMC8493552 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Thiophosphonium-Alkyne Cycloaddition Reactions: A Heavy Congener of the Carbonyl-Alkyne Metathesis.

Löwe Pawel P Feldt Milica M Röthel Maike B MB Wilm Lukas F B LFB Dielmann Fabian F

Inorganic chemistry 20210915 19

While the metathesis reaction between alkynes and thiocarbonyl compounds has been thoroughly studied, the reactivity of alkynes with isoelectronic main group R2E=S compounds is rarely reported and unknown for [R2P=S]+ analogues. We show that thiophosphonium ions, which are the isoelectronic phosphorus congeners to thiocarbonyl compounds, undergo [2 + 2]-cycloaddition reactions with different alkynes to generate 1,2-thiaphosphete ions. The four-membered ring speci ...[more]

PMID: 34524817

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