Base-Stabilized Amidodiarsenes:  Synthesis, Structure, and Theoretical Studies

Abstract

The guanidinato- or amidinato-bridged diarsenes [As2{mu-(ArN)2CR}2] (Ar = C6H3Pri2-2,6; R = N(C6H11)2, NPri2, or But) have been prepared by reduction of the corresponding As(III) precursors, [Cl2As{kappa2-N,N'-(ArN)2CR}]. Theoretical studies suggest that the As-As bonds of the dimers have significant double-bond character, the sigma and pi components of which are derived mainly from As p orbital overlaps.

Synthesis of the Sterically Related Nickel Gallanediyl Complexes [Ni(CO)3(GaAr′)] (Ar′ = C6H3-2,6-(C6H3-2,6-iPr2)2) and [Ni(CO)3(GaL)] (L = HC[C(CH3)N(C6H3-2,6-iPr2)]2): Thermal Decomposition of [Ni(CO)3(GaAr′)] to give the Cluster [Ni4(CO)7(GaAr′)3]

“…The Ni-Ni distances are between 2.361(10) and 2.628(11) Å . A similar range of Ni-Ni distances was reported for Ni 4 (CO) 6 (GaCp*) 4 [13,17,[39][40][41]. Two of the six edges of the Ni 4 tetrahedron are bridged by a l-GaAr 0 fragment.…”

Synthesis and characterization of the unusual cluster [Ni2(GaAr′)2(η1:η1-μ2-C2H4)]: Ready addition of ethylene to Ni(COD)(GaAr′)2 at 25 °C and 1 atmosphere

“…1. The Ga(1)-NieGa(2) angle is 101.64 (4) which is similar to that in the bis gallium (I) triazenido derivative Ni(COD) [Ga{(N(Ar) 2 )CNR 2 }] 2 (Ar¼ C 6 H 3 Pr i 2 -2,6; R ¼ cyclohexyl) gallanediyl complex [15]. The GaeNi bond lengths 2.201(4) and 2.205(4) Å are among the shortest bond distances reported for gallanediyl nickel species (usual range 2.329(9)e2.476(10) Å) [16], which is presumably due to the two-coordination at gallium and the good s-donor character of the GaAr' ligand [16,17].…”

Cyclo-Pnicta-triazanes: Biradicaloids or Zwitterions?

“…(2), 2.451(2) Å). Judged from the molecular geometry, the compounds 2 are closely related to known species incorporating guanidinate or amidinate substituents on pnictogen chloride moieties, which were investigated by the groups of Dehnicke, 41 Jones, 42 Schulz, 43 and Ragogna. 44 In 2E (E = As, Sb, Bi), a contact within the sum of van der Waals radii (E···centroid 3.234, 3.166, 2.971 Å) indicates additional stabilization due to weak interactions with the mesityl groups.…”