136238-07-8Relevant academic research and scientific papers
Synthesis and structural characterization of trimethylphosphine complexes of technetium(III)
Watson, Patricia L.,Albanese, Joseph A.,Calabrese, Joseph C.,Ovenall, Derick W.,Smith, Richard G.
, p. 4638 - 4643 (2008/10/08)
The first structurally characterized technetium(III) complexes containing trimethylphosphine as a ligand are reported. A novel cationic technetium(III) phosphine hydride complex was prepared by reaction of [Tc(S-tu)6][PF6]3 (tu = η1-S=C(NH2)2] with excess trimethylphosphine in methancl. The complex, [TcH{η2-N,S-NHC(NH2)S}(PMe3) 4][PF6] (1) was characterized spectroscopically and crystallographically, and shown to contain the unusual bidentate ligand [η2-N,S-NHC(NH2)S]- and a hydride ligand. Stirring 1 in methanol-d4 led to formation of a spectroscopically identified technetium(III) deuteride, [TcD{η2-N,S-NDC(ND2)S}(PMe3) 4][PF6]. Crystallographic data for 1 are as follows: monoclinic, Cc, a = 9.305 (2) A?, b = 16.726 (2) A?, c = 19.951 (3) A?, β = 91.24°, V = 3104.4 A?3, Z = 4, R = 0.062 (R2 = 0.060) for 2043 observed reflections having Fo > 3σ(Fo). Reaction of a Tc(V) substrate, [NBu4][TcOCl4], with excess trimethylphosphine yielded mer-TcCl3(PMe3)3 (2). Crystals of 2 suitable for X-ray analysis were obtained by cocrystallizing 2 with triphenyl isocyanurate, [(PhNCO)3]. The resulting material, [mer-TcCl3(PMe3)3)][(PhNCO)3], crystallized in the orthorhombic space group Pnma in a unit cell of dimensions a = 18.461 (1) A?, b = 13.934 (2) A?, c = 14.035 (1) A?, V = 3610.3 A?3, and Z = 4, with R = 0.044 (Rw = 0.039) for 3699 observed reflections having Fo > 3σ(Fo). The closest intermolecular distances revealed no bonding between the two components in the crystal, 2 and [(PhNCO)3].
