N‐Heterocyclic Carbene and Cyclic (Alkyl)(amino)carbene Adducts of Germanium(IV) and Tin(IV) Chlorides and Organyl Chlorides

Abstract

AbstractA study on the reactivity of N‐heterocyclic carbenes (NHCs) and the cyclic (alkyl)(amino)carbene cAACMe with selected germanium(IV) and tin(IV) chlorides and organyl chlorides is presented. The reactions of the NHCs Me2ImMe, iPr2ImMe and Dipp2Im with the methyl chlorides ECl2Me2 afforded the adducts NHC ⋅ ECl2Me2 (E=Ge (1), Sn (2)), NHC=Me2ImMe (a), iPr2ImMe (b), Dipp2Im (c)). The reaction of Me2ImMe with GeCl4 led to isolation of Me2ImMe ⋅ GeCl4 (3), the reaction of iPr2ImMe with SnCl4 in THF afforded the THF adduct iPr2ImMe ⋅ SnCl4 ⋅ THF (4). Dipp2Im ⋅ GeCl2Me2 (1 c) isomerized into the backbone coordinated imidazolium salt [aDipp2Im ⋅ GeClMe2][Cl] (5) upon thermal treatment. The reactions of cAACMe with (i) ECl2R2 (E=Ge, Sn) gave the adducts cAACMe ⋅ ECl2R2 (R=Me: E=Ge (6); Sn (7); Ph: E=Ge (8)), with (ii) GeClMe3 and GeCl4 the salts [cAACMe ⋅ GeMe3][Cl] (9) and [cAACMeCl][GeCl3] (10), and (iii) with SnCl4 the salt [cAACMeCl][SnCl3] (11) and the adduct cAACMe ⋅ SnCl4 (12). Reduction of 2 a with KC8 afforded the NHC‐stabilized stannylene Me2ImMe ⋅ SnMe2 13, reduction of 7 with either KC8 or 1,4‐bis‐(trimethylsilyl)‐1,4‐dihydropyrazin in the presence of SnCl2Me2 yielded cAACMe ⋅ SnMe2 ⋅ SnMe2Cl2 (14).