Cis/Trans Isomerization and Conformational Properties of 2,4-Bis(primary amino)-1,3,2,4-Diazadiphosphetidines

Syntheses and crystal structures of mono- and bi-metallic zinc compounds of symmetrically- and asymmetrically-substituted bis(amino)cyclodiphosph(V)azanes

“…The chelation of an ethylzinc moiety by both amido groups is not unexpected, but the coordination by the phosphoryl oxygen atoms is unusual and, as far as we know, unprecedented for this ligand system. The threecoordinate zinc atom has a perfectly trigonal-planar coordination environment and forms two slightly asymmetrical Zn-N bonds (2.028(4) and 2.047 (4) A) that are only insignificantly longer than those of related amido-coordinated zinc ions [17,27,28]. The second zinc atom (Zn1) is in a distorted ZnO 3 C environment.…”

“…The bis(amino)cyclodiphosph(V)azanes cis-[(RHN)-E@P(l-N t Bu) 2 P@E(NHR)] (R ¼ t Bu, Ar; E ¼ O, S, Se, NR) (A, Chart 1) are well-known tetradentate molecules [3][4][5], whose coordination chemistry has only recently been systematically investigated [6]. These ambidentate ligands chelate metal moieties as bis(amido) (N ,N 0 ) ligands above the heterocycle (B) [7] as bis(chalcogenido) (E,E 0 ) ligands below the heterocycles (C) [8], or as a combination of both, namely as bis(amido)/bis(chalcogenido) ligands, i.e., N ,N 0 and E,E 0 (D) [9,10].…”

Synthesis and Derivatization of the Bis(amido)‐λ3‐cyclodiphosphazanes cis‐[R′(H)NP(μ‐NR)]2, Including a Rare Example, trans‐[tBu(H)N(Se)P(μ‐NCy)]2, Showing Intermolecular Se···H–O Hydrogen Bonding

“…The substituents on N and P have been removed for clarity. worth noting that only the (exo,endo) isomer was observed in all of the structurally reported [17,19] chalcogenide derivatives of the type cis-[tBuNP(E)(NHR)] 2 (R = Ph, tBu, E = S, Se). The (endo,endo) conformational arrangement was possibly favored in the solid state for 13 because of the presence of the lattice water molecules and the consequent formation of a linear hydrogen bonding network (Figure 4).…”

Bis(amido)cyclodiphosph(III)azane Complexes of Yttrium and the Lanthanides

“…[15,16] Their preparation is usually based on the reaction of PCl 3 with an excess of a free amine. [17,18] Today cyclodiphos-A C H T U N G T R E N N U N G phA C H T U N G T R E N N U N G (III)azanes are well established as anionic N-donor ligands in main-group [18,19,20] and early-transition-metal chemistry. [21,22] Group 4 complexes of these ligands have been shown to have high activities in ethylene polymerization in the presence of methylaluminoxane (MAO).…”