Cluster synthesis via aggregation: synthesis and solution and solid-state characterization of sulfur-capped group 6 metal carbonyl clusters Academic Article uri icon

abstract

  • The trinuclear clusters [PPN]2[M3(CO)12S] (M = Cr, Mo, W) have been prepared by a stepwise aggregation of [M(CO)5] fragments about a sulfur atom template, with subsequent loss of three carbonyl ligands concomitant with the formation of three metal-metal bonds. The stepwise assembly process allows for the synthesis of the mixed-metal clusters [PPN]2[Cr2W(CO)12S], [PPN]2[Mo2W(CO)12S], and [PPN]2[CrMoW(CO)12S]. These compounds have been characterized by infrared and 13C NMR spectroscopies, and X-ray crystal structures of the Cr3, Mo3, and Mo2W clusters have been determined. [PPN]2[Cr3(CO)12S]: space group P21/c, a = 25.732 (6) Å, b = 14.255 (5) Å, c = 21.689 (4) Å, β = 96.16 (3)°, V= 7909.8 Å3, Z = 4. [PPN]2-[Mo3(CO)12S]: space group P21/c, a = 25.953 (4) Å, b = 14.329 (2) Å, c = 21.830 (5) Å, β = 96.26 (2)°, V = 8069.2 Å3, Z = 4. [PPN]2[Mo2W(CO)12S]: space group P21/c, a = 25.912 (6) Å, b = 14.275 (3) Å, c = 21.871 (3) Å, β = 96.23 (2)°, V = 8042.0 Å3, Z = 4. The trinuclear clusters can add a fourth [M(CO)5] unit to produce the tetranuclear derivatives [PPN]2-[M4(CO)17S]. In solution, the carbonyl ligands of both the tri-and tetranuclear clusters are extremely fluxional. Temperatures as low as -110 °C must be achieved to freeze out the various processes. © 1988, American Chemical Society. All rights reserved.

author list (cited authors)

  • Darensbourg, D. J., Zalewski, D. J., Sanchez, K. M., & Delord, T.

citation count

  • 22

publication date

  • March 1988