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A short, versatile route towards benzothiadiazinyl radicals.

ABSTRACT: A family of substituted 1,2,4-benzothiadiazine 1-chlorides have been prepared by treatment of N-arylamidines in neat thionyl chloride at reflux. The S(iv) 1-chlorides are readily reduced under mild conditions to persistent 1,2,4-benzothiadiazinyl radicals which have been characterised by EPR spectroscopy and cyclic voltammetry. Crystallographic studies on isolated radicals indicate that the radicals dimerise via pancake bonding in the solid-state, resulting in spin-pairing and net diamagnetism.

SUBMITTER: Borys AM

PROVIDER: S-EPMC8694340 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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A short, versatile route towards benzothiadiazinyl radicals.

Borys Andryj M AM Clark Ewan R ER Saines Paul J PJ Alberola Antonio A Rawson Jeremy M JM

Chemical science 20211123 1

A family of substituted 1,2,4-benzothiadiazine 1-chlorides have been prepared by treatment of <i>N</i>-arylamidines in neat thionyl chloride at reflux. The S(iv) 1-chlorides are readily reduced under mild conditions to persistent 1,2,4-benzothiadiazinyl radicals which have been characterised by EPR spectroscopy and cyclic voltammetry. Crystallographic studies on isolated radicals indicate that the radicals dimerise <i>via</i> pancake bonding in the solid-state, resulting in spin-pairing and net ...[more]

PMID: 35059163

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