TY - JOUR
T1 - Steric Control of Aggregation in Neutral Silver(I) Thiolates, [AgSR]n. Crystal and Molecular Structures of [AgSCH(SiMe3)2]8, a Discrete Molecular Biscycle of Weakly Interacting [AgSCH(SiMe3)2]4 Units, and of [AgSC(SiphMe2)3]3 and [AgSC(SiMe3)3]4, Discrete Molecular Monocycles Containing Linearly Coordinated Silver(I) and Doubly Bridging Mercapto Sulfur Donors from Novel Sterically Hindered Thiolate Ligands. A Comparison with the Nonmolecular Structure of [Ag4{SCH2(SiMe3)}3]n(OMe)n1
AU - Tang, Kaluo
AU - Aslam, Mohammad
AU - Block, Eric
AU - Nicholson, Terrence
AU - Zubieta, Jon
PY - 1987
Y1 - 1987
N2 - By the use of a novel series of sterically hindered thiolate ligands, (RR′R″Si)nCH3–n the colorless silver–thiolate complexes [AgSC(SiMe2Ph)3]3 (5a) and [AgSC(SiMe3)3]4 (4a) and the yellow species [AgSCH(SiMe3)2]8 (3a) and [Ag4{SCH2-(SiMe3)}3(OCH3)]n (2a) have been synthesized and structurally characterized. The structure of 5a consists of a discrete nonplanar six-membered cycle of alternating silver and sulfur atoms, Ag3S3, exhibiting no secondary interactions between trinuclear units. In contrast, the structure of 4a consists of a planar eight-membered cycle, Ag4S4, and exhibits unstrained digonal Ag–S coordination, unperturbed by secondary Ag…S interactions. The results suggest that a degree of control of aggregation may be introduced by employing ligands possessing sufficient steric bulk. Furthermore, the reduction of ligand steric hindrance in -SCH(SiMe3)2 has profound structural consequences as illustrated by the structure of 3a, which consists of two weakly interacting [AgSCH(SiMe3)2]4 cycles, facing each other and connected by secondary Ag…S interactions, producing a T-shaped geometry about the Ag centers. Further reduction in the steric bulk of the ligand results in the polymeric structure of 2a. The complex three-dimensional polymer may be described in terms of kinked chains of fused octanuclear Ag4S4 cyclic links cross-linked through bridging Ag4S4 monocycles. Crystal data: for 5a, triclinic P1 α = 11.236 (2) Å, b = 16.445 (3) Å, c = 25.686 (4) Å, α = 92.79 (1)°, ß = 97.52 (1)°, γ = 108.77 (1)°, V = 4434.2 (9) Å3, Dcalcd = 1.34 g cm–3 for Z = 2, R = 0.061 for 9537 reflections; for 4a, orthorhombic Pbca, a = 17.478 (3) Å, b = 28.314 (4) Å, c = 29.706 (4) Å, V = 14700.6 (12) Å3, Dcalcd = 1.28 g cm–3 for Z = 8, R = 0.069 for 2759 reflections; for 3a, monoclinic C2/c, α = 18.339 (4) Å, b = 24.623 (4) Å, c = 24.473 (4) Å, ß = 96.74 (1)°, V = 10974.6 (11) Å3, Dcalcd = 1.45 g cm–3 for Z = 4, R = 0.063 for 3919 reflections; for 2b, monoclinic C2/c, α = 17.023 (3) Å, b = 29.470 (5) Å, c = 23.372 (4) Å, ß = 104.21 (1)°, V = 11366.2 (14) Å3, Dcalcd = 1.92 g cm–3 for Z = 16, R = 0.069 for 1366 reflections.
AB - By the use of a novel series of sterically hindered thiolate ligands, (RR′R″Si)nCH3–n the colorless silver–thiolate complexes [AgSC(SiMe2Ph)3]3 (5a) and [AgSC(SiMe3)3]4 (4a) and the yellow species [AgSCH(SiMe3)2]8 (3a) and [Ag4{SCH2-(SiMe3)}3(OCH3)]n (2a) have been synthesized and structurally characterized. The structure of 5a consists of a discrete nonplanar six-membered cycle of alternating silver and sulfur atoms, Ag3S3, exhibiting no secondary interactions between trinuclear units. In contrast, the structure of 4a consists of a planar eight-membered cycle, Ag4S4, and exhibits unstrained digonal Ag–S coordination, unperturbed by secondary Ag…S interactions. The results suggest that a degree of control of aggregation may be introduced by employing ligands possessing sufficient steric bulk. Furthermore, the reduction of ligand steric hindrance in -SCH(SiMe3)2 has profound structural consequences as illustrated by the structure of 3a, which consists of two weakly interacting [AgSCH(SiMe3)2]4 cycles, facing each other and connected by secondary Ag…S interactions, producing a T-shaped geometry about the Ag centers. Further reduction in the steric bulk of the ligand results in the polymeric structure of 2a. The complex three-dimensional polymer may be described in terms of kinked chains of fused octanuclear Ag4S4 cyclic links cross-linked through bridging Ag4S4 monocycles. Crystal data: for 5a, triclinic P1 α = 11.236 (2) Å, b = 16.445 (3) Å, c = 25.686 (4) Å, α = 92.79 (1)°, ß = 97.52 (1)°, γ = 108.77 (1)°, V = 4434.2 (9) Å3, Dcalcd = 1.34 g cm–3 for Z = 2, R = 0.061 for 9537 reflections; for 4a, orthorhombic Pbca, a = 17.478 (3) Å, b = 28.314 (4) Å, c = 29.706 (4) Å, V = 14700.6 (12) Å3, Dcalcd = 1.28 g cm–3 for Z = 8, R = 0.069 for 2759 reflections; for 3a, monoclinic C2/c, α = 18.339 (4) Å, b = 24.623 (4) Å, c = 24.473 (4) Å, ß = 96.74 (1)°, V = 10974.6 (11) Å3, Dcalcd = 1.45 g cm–3 for Z = 4, R = 0.063 for 3919 reflections; for 2b, monoclinic C2/c, α = 17.023 (3) Å, b = 29.470 (5) Å, c = 23.372 (4) Å, ß = 104.21 (1)°, V = 11366.2 (14) Å3, Dcalcd = 1.92 g cm–3 for Z = 16, R = 0.069 for 1366 reflections.
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U2 - 10.1021/ic00257a007
DO - 10.1021/ic00257a007
M3 - Article
AN - SCOPUS:0000070920
SN - 0020-1669
VL - 26
SP - 1488
EP - 1497
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 10
ER -