POLYSULFONYL AMINES .24. PREPARATION AND CRYSTAL-STRUCTURES OF BIS(DIMESYLAMINO)DIMETHYL SILANE AND BIS(DIMESYLAMINO)DIMETHYL STANNANE

The new compounds (CH3)2E[N(SO2CH3)2]2 with E = Si (3), m.p. 162-degrees-C, and E = Sn (4), m.p. 194-196-degrees-C, were prepared by metathesis of AgN(SO2CH3)2 with (CH3)2ECl2 and subjected to X-ray structure determinations. 3 crystallizes in the monoclinic space group C2/c with a = 1714.3(4), b = 679.6(2), c = 1389.9(4) pm, beta = 97.50(2)-degrees and Z = 4, 4 in the same space group with a = 2093.8(8), b = 1320.7(6), c = 1443.9(6) pm, beta = 124.28(3)-degrees and Z = 8. The crystals of both compounds consist of discrete monomeric molecules, in which the central atom E is bonded to two carbon and two nitrogen atoms in an approximately tetrahedral geometry for 3 [angles at Si in the range (105.5...111.9)-degrees] and in a severely distorted tetrahedral arrangement in 4 [CSnC 128.8-degrees; NSnN 107.8-degrees; NSnC in the range (99.9...109.4)-degrees]. Details of the molecular structures suggest that in each molecule two intramolecular E...O dipole-dipole interactions are stereochemically significant [Si...O 291.4 pm (2x); Sn...O 300.9 and 303.1 pm]. The molecule of 3 displays an exact, that of 4 an approximate twofold symmetry.