Silver(I) complexes of the potentially chelating olefinic ligands 2,2-dimethylbut-3-enyl methyl sulphide and 2,2-dimethyl-2-silabut-3-enyl methyl sulphide. Crystal structure analysis of bis(2,2-dimethylbut-3-enyl methyl sulphide)silver(I) tetrafluoroborate, (2,2-dimethylbut-3-enyl methyl sulphide)silver(I) perchlorate, (2,2-dimethylbut-3-enyl methyl sulphide)nitratosilver(I), and (2,2-dimethylbut-3-enyl methyl sulphide)-trifluoroacetatosilver(I)

Abstract

1981 481 Silver( I) Complexes of the Potentially Chelating Olef inic Ligands 2 2 -Dimethylbut-3-enyl Methyl Sulphide and 2.2-Dimethyl-2-silabut-3-enyl Methyl Sulphide. Crystal Structure Analysis of Bis(2.2-dimethylbut-3enyl methyl sulphide)silver(l) Tetrafluoroborate, (2.2-Dimethylbut-3-enyl methyl sulphide)silver(i) Perchlorate, (2.2-Dimethylbut-3-enyl methyl sulphide)nitratosilver( I), and (2,2-Dimethyl but-3-enyl methyl sulphide)trifluoroacetatosilver(i)

Silver–Ethene Complexes [Ag(η2‐C2H4)n][Al(ORF)4] with n=1, 2, 3 (RF=Fluorine‐Substituted Group)

“…However, all the C=C bond lengths were shorter or similar to the converged bond length of free gaseous ethene established in 2006 (133.05(10) pm). [72] Similar observations, often also including the 3s criterion, were made for many other known silverethene complexes collected in Table 1, but not for complexes of substituted alkenes [21,23,81,82] (see also 2). According to current models for the bonding in alkene complexes, the bond lengths can be elongated but not shortened upon coordination.…”

“…: A = BF 4 , ClO 4 , SO 3 CF 3 ) with chelating ligands such as 1,5-hexadiene, [28] norbornadiene, [22] 1,4,7-cyclononatriene, [23] 1,3,5,7-cyclooctatetraene (and derivatives), [20,24,25,50,51] bullvalene, [26] tetraphenylethene, -butadiene [19] and other substituted alkenes. [17,18,21,27,52] However, these olefins are solids or liquids and, therefore, the entropic contribution to dissociation (and thus decomposition) is much smaller than that for the lightest parent olefin C 2 H 4 . Moreover, it was shown by quantum chemistry [13] that the replacement of each hydrogen atom in C 2 H 4 by a methyl group increases the silver complexation enthalpy by about 20 to 22 kJ mol…”

“…[83] This effect likely also accounts for the short bond length of crystalline C 2 H 4 itself observed by X-ray at 85 K (131.31(3) pm). [49] In solid 2 as well as other substituted olefin complexes [21,23,81,82] this libration is restricted and sensible C=C bond lengths were observed.…”