Elke Wieland

Polysulfonylamine: XLVII. Darstellung und Kristallstrukturanalyse der ionischen Verbindung catena-Poly[(μ-4,4′-bipyridin)trimethylzinn]-dimesylamid-Acetonitril (1/1)

Abstract Me3SnN(SO2Me)2 · 4,4′-bpy is obtained as an amorphous powder by treating a suspension of Me3SnN(SO2Me)2 in Et2O with one equivalent of 4,4′-bipyridine. It crystallizes from MeCN as a labile (1/1)-solvate. The crystallographic data of the latter at −95°C are: monoclinic, space group P21/n, a 930.9(2), b 1105.9(4), c 2227.4(7) pm, β 92.27(2)°, U 2.2910 nm3, Z = 4. The crystal packing consists of linear-polymeric [Me3Sn(μ-4,4′-bpy)-]nn+ cations in which the monomers are related by a glide plane, discrete (MeSO2)2N− anions, and non-coordinating MeCN molecules. The angle between the C5N planes of the bipyridine is 32°. The tin atom has a trigonal-bipyramidal environment with two apical nitrogen atoms: SnN 241.1/242.0, SnC 211.9–213.0 pm; NSNN 176.8, CSNC 115.9123.9, NSNC 87.0–94.0°.

Polysulfonylamine: XXXVIII. Darstellung und Festkörperstruktur von Bis(trimethylzinn)-dimesylamid-hydroxid [Me3Sn{μ-(MeSO2)2N}Me3Sn(μ-OH)]n☆

The title compound 1 is obtained from equimolar amounts of Me3SnN(SO2Me)2 (2) and Me3SnOH in ethanol or by partial hydrolysis of 2 in CH2Cl2 solution and in presence of a nitrogen base, e.g. pyridine. 1 crystallizes in the triclinic space group P1 with (at −95°C) a = 825.4(3), b = 856.2(3), c = 1341.6(5) pm, α = 81.97(3), β = 74.72(3), λ = 79.75(3)°, U = 0.8958 nm3, Z = 2. The structure consists of infinite chains, in which Me3Sn groups are bridged by alternating O(H) and (α-O, ω-O)-bonded dimesylamide groups. Antiparallel chains are interconnected by OH⋯N hydrogen bonds to form a “ladder” structure. There are two independent tin atoms. The SnO(H) distances are 211.8(2) and 212.6(2) pm, the SnO(S) distances 268.2(2) and 253.3(2) pm, the O(H)SnO(S) angles 174.5(1) and 173.8(1)°, and the SnO(H)Sn angle is 136.9(1)°. In the trigonal-bipyramidal (C3O2) environment of the tin atoms, the CSNC angles are slightly smaller than 120°, the O(H)SnC angles significantly greater than 90°, and the O(S)Sn C angles correspondingly smaller than 90°. Thus, the chain structure might reasonably be viewed as consisting of [(Me3Sn)2OH]+ ions alternating with [(MeSO2)2N]− ions.

Polysulfonylamine, XXXVI Trimethylsilyl-dimesylamin: Darstellung, NMR-spektroskopische Charakterisierung und Reaktionsfähigkeit als Silylierungsreagens / Polysulfonylamines, XXXVI Trimethylsilyl Dimesylamine: Preparation, NMR-Spectroscopic Characterization, and Reactivity as a Silylating Agent

(CH3)3SiN(SO2CH3)2 (1), m. p. 69-70 °C, is obtained by metathesis of AgN(SO2CH3)2 with (CH3)3SiCl (improvement of a known procedure) or, more conveniently, by silylation of HN(SO2CH3)2 with [(CH3)3Si]2NH. The 1H, 13C and 29Si NMR solution spectra and the 29Si NMR solid-state spectrum suggest the constitution of 1 in solution (CDC13, CD2C12, CDCl2–CDCl2) to be an equilibrium mixture of the N-silylated form (CH3)3Si–N(SO2CH3)2 (I) and the O-silylated form (CH3)3Si–O–S(O)(CH3)=NSO2CH3 (II) in a molar ratio of 2:1 at room temperature, whereas in the known crystal structure of 1 only form I is present. The solid-state NMR experiment acted as a bridge between X-ray crystallography and solution-state NMR, enabling assignments of the resonances to be made with confidence to the tautomers. At room temperature, form II undergoes a rapid intramolecular 1.5-migration of silicon between oxygen centers of the two sulfonyl groups. As shown by kinetic measurements using 1H NMR spectroscopy, 1 is a highly reactive agent for silylating ketones in the presence of triethylamine. Hydroxy and thiol functions, even when sterically hindered, are silylated by 1 in uncatalyzed reactions. It is further shown that HN(SO2CH3)2 is an efficient catalyst for silylations with [(CH3)3Si]2NH.

Polysulfonylamine, VIII [1] Ein Molekül mit einer extrem langen Silicium-Stickstoff-Bindung. Festkörperstrukturen von N-Trimethylsilyl- und N-Methyl-dimesylamin / Polysulfonylamines, VIII [1] A Molecule with an Extremely Long Silicon-Nitrogen Bond. Solid State Structures of N-Trimethylsilyl- and N-Methyl-dimesylamine

Abstract The crystal and molecular structures of two dimesylamine derivatives, RN(SO2CH3)2, (R = Si(CH3)3 (1a), R-CH3 (1b)) were determined. Com pound 1a displays a very long Si-N bond which is well outside the range normally found in comparable com pounds (185.1 pm, mean value for two crystallographically independent m olecules). The unusually large bond length can be explained by the absence of (d -p)π interactions between silicon and nitrogen. In both com pounds the bonding geometry around the nitrogen atoms is essentially planar