Synthese von vier- und achtgliedrigen Heterocyclen, die Schwefel, Stickstoff und Phosphor enthalten, und die Röntgenstrukturanalyse eines phosphorhaltigen achtgliedrigen SN-Ringes
Synthesis of four- and eight-membered heterocycles containing sulfur, nitrogen and phosphorus and the X-ray structure of a phosphorus-containing eight-membered SN-ring
- Eight-membered rings of the composition [SO2(NR)2PR′]2 3a-d with R = CH3, C2H5, and R′ = CH3, C6H5, were prepared from substituted sulfamides and dichlorophosphanes in the presence of a tertiary amine. These molecules were characterized on the basis of 1H and 31P NMR investigations and of mass spectra. 3 a reacts with phosphorus pentachloride to yield the spirocyclic derivative 4 with the phosphorus atom in the center of two four-membered rings. Methyliodide reacts with 3 a and 3 b under opening of the eight- membered ring and formation of phosphonium salts. The structure of 3 b is discussed in detail. 8b crystallizes in the orthorhombic space group Pna 21 with a = 12.60(0), b = 13.27(1), c = 12.62(4) Å.