Darstellung von Tetramethylammoniumazidsulfit und Tetramethylammoniumcyanat-Schwefeldioxid-Addukt, [(CH3)4N]+[SO2N3]-, [(CH3)4N]+ [SO2OCN]- und Kristallstruktur von [(CH3)4N]+[SO2N3]-

Abstract

Professor Karl Otto Christe zum 65. Geburtstag gewidmet Inhaltsu È bersicht. Tetramethylammoniumazid bildet mit Schwefeldioxid ein Azidsulfit, das durch NMR-und Schwingungsspektroskopie sowie eine Einkristallstrukturanalyse charakterisiert wurde. [(CH 3 ) 4 N] + [SO 2 N 3 ] ± kristallisiert in der monoklinen Raumgruppe P2 1 /c mit a = 551,3(1) pm, b = 1095,2(1) pm, c = 1465,0(1) pm, b = 100,63(1)°und Z = 4. Im Kristall liegen starke S±N-Kontakte zwischen den N 3± -Anionen und den SO 2 -Moleku È len vor, die mit 200,5(2) pm deutlich la È nger als eine entsprechende kovalente Einfachbindung sind. Die Strukturparameter werden mit ab initio berechneten Werten verglichen. Das dargestellte Addukt zwischen Tetramethylammoniumcyanat und SO 2 wurde durch NMR-und Schwingungsspektroskopie charakterisiert und die Struktur mit ab initio Methoden berechnet.Abstract. Tetramethylammonium azide forms with sulfur dioxide an azidosulfite salt. It is characterized by NMR and vibrational spectroscopy and the crystal structure analysis. [(CH 3 ) 4 N] + [SO 2 N 3 ] ± crystallizes in the monoclinic space group P2 1 /c with a = 551.3(1) pm, b = 1095.2(1) pm, c = 1465.0(1) pm, b = 100.63(1)°, and four formula units in the unit cell. The crystal structure possesses a strong S±N interaction between the N 3± anions and the SO 2 molecules. The S±N distance of 200.5(2) pm is longer than a covalent single S±N bond. The structure is compared with ab initio calculated data. Furthermore an adduct of tetrametylammonium cyanate and sulfur dioxide is reported. It is characterised by NMR and vibrational spectroscopy. The structure is calculated by ab initio methods.

The (SO2)2N3- Anion

“…In the (SO 2 ) 2 N 3 - anion, the two SO 2 groups are bound to the same terminal nitrogen atom of N 3 - . The azide group is essentially linear with a significant difference in the N−N bond lengths (1.141(6) and 1.219(6) Å), which are very similar to those found in [N(CH 3 ) 4 ][SO 2 N 3 ] (1.144(2) and 1.214(2) Å) . In the (SO 2 ) 2 N 3 - anion, one S−N bond (2.201(5) Å) is significantly shorter than the second one (2.427(4) Å).…”

“…In the (SO 2 ) 2 N 3 - anion, one S−N bond (2.201(5) Å) is significantly shorter than the second one (2.427(4) Å). However, both S−N bonds are longer than that found for the SO 2 N 3 - anion in [N(CH 3 ) 4 ][SO 2 N 3 ] (2.005(2) Å) …”

“…These adducts can be viewed as halosulfites and pseudo-halosulfites. The strength of the bond between these anions and SO 2 was found to decrease with increasing anion size. ,, In the SO 2 F - anion, for example, the S−F bond is basically a single bond, while the S-anion bonds in SO 2 I - and SO 2 SCN - are best described as contacts or secondary bonds …”

“…Sulfur dioxide has been extensively used as a nonaqueous inorganic solvent, − and many SO 2 solvates of metal cations have been structurally well characterized by X-ray crystallography . Halide and pseudo-halide anions, such as F - , , Cl - , , Br - , I - , , CN - , SCN - , OCN - , and recently N 3 - , , were also found to form adducts with SO 2 in a 1:1 ratio. These adducts can be viewed as halosulfites and pseudo-halosulfites.…”

Fundamental chemistry of binary S,N and ternary S,N,O anions: analogues of sulfur oxides and N,O anions

“…23 This transformation is attributed to the remarkably long S-N bond in M[SO2N3] salts (M = Cs, 1.981(12) Å; 23 M = Me4N, 2.005(2) Å). 24 Typical S-N bond lengths are given in Table 2. For comparison, the S-N bond in Cs[SO3N3] is substantially shorter (by 0.23 Å) as a result of the stronger Lewis acidity of SO3 compared to that of SO2.…”