Group 14 Metal Terminal Phosphides: Correlating Structure with |J_MP|

Abstract

A series of heavier group 14 element, terminal phosphide complexes, M(BDI)(PR(2)) (M = Ge, Sn, Pb; BDI = CH{(CH(3))CN-2,6-iPr(2)C(6)H(3)}(2); R = Ph, Cy, SiMe(3)) have been synthesized. Two different conformations (endo and exo) are observed in the solid-state; the complexes with an endo conformation have a planar coordination geometry at phosphorus (M = Ge, Sn; R = SiMe(3)) whereas the complexes possessing an exo conformation have a pyramidal geometry at phosphorus. Solution-state NMR studies reveal through-space scalar coupling between the tin and the isopropyl groups on the N-aryl moiety of the BDI ligand, with endo and exo exhibiting different J(SnC) values. The magnitudes of the tin-phosphorus and lead-phosphorus coupling constants, |J(SnP)| and |J(PbP)|, differ significantly depending upon the hybridization of the phosphorus atom. For Sn(BDI)(P{SiMe(3)}(2)), |J(SnP)| is the largest reported in the literature, surpassing values attributed to compounds with tin-phosphorus multiple-bonds. Low temperature NMR studies of Pb(BDI)(P{SiMe(3)}(2)) show two species with vastly different |J(PbP)| values, interpreted as belonging to the endo and exo conformations, with sp(2)- and sp(3)-hybridized phosphorus, respectively.

Reactivity of β-Diketiminato Magnesium Alkyl Complexes: Heterocumulenes and Phosphanes

“…[(BDI)M(PPh 2 )], where a lone-pair takes the place of a coordinated THF molecule on the metal centre. [47] In both groups, the degree of pyramidalisation at phosphorus increases as the group is descended.…”

Bi−P Bond Homolysis as a Route to Reduced Bismuth Compounds and Reversible Activation of P4

“…Keywords: bismuth ·b ond homolysis ·main-group radicals · P 4 activation ·phosphanides (13), N1-Bi-P1 98.10(10), N2-Bi-P1 95.35-(9), P2-P1-P2' 58.88 (7), Bi-P1-P2 96.70(6), Bi-P1-P2' 96.88(6), P1-P2-P1' 77.56 (7), P1-P2-P2' 60.87(6), P2'-P2'-P1' 60.25 (5).…”

“…We reasoned that these products form through homolytic cleavage of the BiÀPb ond in the intermediate species," Bi(NON Ar )(PPh 2 )". [13] To investigate whether as teric conflict between the [NON Ar ]l igand and the phosphanide promotes decomposition, Bi(NON tBu )Cl (3) was synthesized. [14] Reaction of 3 with LiPPh 2 also proceeded with formation of tetraphenyldiphosphane.H owever,t he reduced size of the ancillary ligand allowed the Bi II product to dimerize,a ffording dibismuthane [Bi(NON tBu )] 2 (4).…”

Syntheses, Structures and Reactivity of Terminal Phosphido Complexes of Iron(II) Supported by a β‐Diketiminato Ligand

“…In these cases, phosphorus atom is connected only to one metal center and can exhibit either pyramidal geometry with one lone pair or planar geometry with the lone pair participating in π bonding , . It should be noted that, among the high number of bridged phosphido complexes,, there are many reports of transition metal complexes featuring non‐bridging, terminal phosphido ligands,, including some supported by nacnac ligands . However, only a handful of known terminal phosphido complexes, incorporate iron and, in most cases, these complexes are supported by carbonyl or cyclopentadienyl co‐ligands.…”