Selenium Heterocycles: Reactions of SeX₄ (X = Cl, Br) with the Enamine Form of β‐Diketiminato Ligands

Abstract

Treatment of SeX4 (X = Cl, Br) with either MesnacnacLi(nacnac = [{N(Ar)C(Me)}2CH]–, Ar = Mes = C6H2Me3‐2,4,6) or DmpnacnacLi (Ar = Dmp = C6H3Me2‐2,6) affords four new SeII six‐membered heterocycles, [MesnacnacHCl2SeCl] (2), [MesnacnacH2Se]+Br– (3), [DmpnacnacH2Cl3Se]+Cl– (4), and [MesnacnacH2(O)Br2Se] (5). All have been characterized in the solid state by X‐ray crystallography. Each of the four complexes is proposed to have formed from the initial reaction of SeX4 with the C–C double bond that results from the enamine form of the ligand, giving rise to an Se–C single bond. Subsequent nucleophilic attack by either the more distant nitrogen atom or the remaining C–C double bond of the enamine form results in the Se heterocycle. In complexes 2, 4, and 5 varying degrees of halogenation of the newly formed heterocycles was observed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The Role of 2,6‐Diaminopyridine Ligands in the Isolation of an Unprecedented, Low‐Valent Tin Complex

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Substitution matters: isolating phosphorus diiminopyridine complexes

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Lewis Base Sequestered Chalcogen Dihalides: Synthetic Sources of ChX2 (Ch=Se, Te; X=Cl, Br)

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