Reaction of 3-dimethylamino-(1,1 -dimethyl) propyl magnesium chloride with tin (IV) and tin (II) chlorides. Stabilization of a SnCl+ cation in the new tin cluster [Me2NCH2CH2C(Me2)SnCl]3 · SnCl2

The reactions of the functional Grignard reagent Me₂ NCH₂CH₂C(Me₂)MgCl (4) with tin tetrachloride, dimethyltin dichloride, and tin (II) chloride are described. From the reactions the compounds bis(3-dimethylamino-1,1-dimethylpropyl) tin dichloride, Me₂NCH₂CH₂C(Me₂)]₂SnCl₂ (5) , dimethyl(3-dimethylamino-1,1-dimethylpropyl) chlorostannane, Me₂ClSnC(Me₂)CH₂CH₂NMe₂ (6) , 1,1,2,2-tetramethyl-1,2-bis(3-dimethylamino-1,1-dimethylpropyl) distannane,Me₂SnC(Me₂)CH₂CH₂NMe₂]₂ (7) , 3-dimethylamino-(1,1-dimethyl)propyl tin (II) chloride, Me₂NCH₂CH₂C(Me₂)SnCl (8) , hexakis(3-dimethylamino-1,1-dimethylpropyl) cyclotristannane, {Me₂NCH₂CH₂C(Me₂)]₂Sn}₃ (9a) , and the tin cluster Me₂NCH₂CH₂C(Me₂)SnCl]₃ · SnCl₂ (10) have been isolated and characterized by means of multinuclear NMR and Mössbauer spectroscopy, and X-ray diffraction. 10 crystallizes in the trigonal space group P3₁ with the unit cell dimensions a 11.938, c 21.873 Å, V 2699.6 ų Z = 3. The structure was refined to a final R value of 0.064. 10 represents a tetranuclear cluster the skeleton of which is composed out of 4 Sn and a bridging Cl. Formally, the central tin atom is a SnCl⁺ cation stabilized by three stannylene units in a Ψ-trigonal bipyramidal environment. The tin-tin bond lengths are 288.2, 287.3 and 315.6 pm. The intramolecular Sn? N interactions amount to 242.8, 247.4 and 221.0 pm.