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

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

Automated summary

This study presents the reactivity of N-heterocyclic carbenes and cyclic carbene with germanium and tin compounds. The findings are important for understanding the properties and applications of these compounds.