Synthesis of the open-shell 3d-transition metal(II) bis(phosphinidenide) [Mn{P(sIDipp)}].

The synthesis and characterization of the first homoleptic open-shell transition metal phosphinidenide is presented. By reacting [MnL] (L = -N(SiMe)) with [(sIDipp)PK] (sIDipp = 1,3-bis(2,6-di-iso-propylphenyl)-imidazolidine-2-ylidene), the formation of [Mn{P(sIDipp)}] instead of the initially expected adduct [KMn{P(sIDipp)}L] is observed. Interestingly, a solvent change from toluene to -pentane leads to the formation of [(sIDipp)PK(EtO)][MnL] after work-up, which can be seen as intermediate in the formation process of [Mn{P(sIDipp)}].

Construction of Inorganic Crown Ethers by s-Block-Metal-Templated Si-O Bond Activation.

We herein report the synthesis, structures, coordination ability, and mechanism of formation of silicon analogs of crown ethers. An oligomerization of D (I) ( D ,=(Me Si O) ) was achieved by the reaction with GaI and MI (M=Li, Na, Mg, Ca, Sr). In these reactions the metal cations serve as template and the anions (I /[GaI ] ) are required as nucleophiles.

Coordination polymers of alkali metal cyclosiloxazanides with one- and two-dimensional structures.

The reaction of O(SiMeCl) with ammonia yielded the cyclic siloxazane O(SiMe)NH (1), which was used as a precursor for the synthesis of siloxazanide-type alkali metal salts. The metalation of 1 with the strong bases BzA (A = Na, K, Rb, Cs and Bz = benzyl) results in different dimensional structures depending on the alkali metal ion used. These results give new insights into framework design with inorganic building blocks and the coordination ability of siloxanes.

Low-Valent Group 14 Phosphinidenide Complexes [({SIDipp}P) M] Exhibit P-M pπ-pπ Interaction (M=Ge, Sn, Pb).

Herein, the synthesis of new low-valent Group 14 phosphinidenide complexes [({SIDipp}P) M] exhibiting P-M pπ-pπ interactions (SIDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolidin-2-ylidene, M=Ge, Sn, Pb), is presented. These compounds were investigated by means of structural, spectroscopic, and quantum-chemical methods. Furthermore, the monosubstituted compounds [(SIDippP)MX] (M=Sn, X=Cl; M=Pb, X=Br) are presented, which show dimeric structures instead of multiple bonding interaction.

Low-Valent Group 14 NHC-Stabilized Phosphinidenide ate Complexes and NHC-Stabilized K/P-Clusters.

The N-heterocyclic carbene (NHC)-stabilized phosphinidenide, SIMesPK [SIMes=1,3-bis(2,4,6-trimethylphenyl)imidazolidine-2-ylidene], was used as an (NHC)P-transfer reagent for the synthesis of the low-valent Group 14 ate complexes K[(SIMesP) E] (E=Ge: 2, Sn: 3, Pb: 4), which were characterized by H NMR, P NMR, IR spectroscopy as well as elemental and X-ray analysis. Furthermore, SIMesPK was used in reactions with potassium amides and alkoxides to form the molecular phosphorus-potassium clusters [K (SIMesP) (hmds) ] [5, hmds=N(SiMe ) ] and [K (SIMesP) (OtBu) ] (6). Finally, the reaction of SIMesPK with Li[Al(OC F ) ] led to the potassium-rich ionic compound [(SIMesP) K ][Al(OC F ) ] (7).

Phosphaalkene-substituted organo-group 15 compounds: synthesis and characterisation of (NHC)P-EtBu (E = P, As, Sb and Bi).

Herein, we present the synthesis and characterisation of new group 15 element compounds with low valent phosphorus atoms as substituents. This new series of compounds includes the heavier group 15 elements and represents the rare group of compounds with a direct P-E bond (E = P, As, Sb and Bi).

An NHC-phosphinidenyl as a synthon for new group 13/15 compounds.

The parent phosphinidene SIMesPH (1) (SIMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) was treated with benzyl potassium to form the metalated species SIMesPK (2), which was used as a synthon for the new group 13/15 cycles and cage compounds [SIMesPGatBu] (3), [SIMesP(GatBu)Cl] (4) and [K(SIMesP)AltBu] (5).

Improved reactivity of a cyclic 13/15 compound by increased steric demand.

Herein we present the synthesis and characterization of the new four-membered Ga/P cycle [tBuGaP(H)SitBuPh], which shows a cis/trans isomerization at ambient temperatures via a ring opening mechanism. The sterically demanding substituents on the phosphorus (-SitBuPh) and gallium (tBu) atoms lead to an unexpected reactivity towards bulky NHC ligands (IMes and IDipp). The resulting Lewis base stabilized monomeric 13/15 compounds feature an unusual binding mode of the carbene ligand.

Cyclic NHC-stabilized silylphosphinoalanes and -gallanes.

Four-membered Al/Ga-P ring systems were prepared by thermal hydrogen elimination between the primary silylphosphine H2PSitBuPh2 and the metal hydride precursors [(Me3N)MH3] (M = Al, Ga). The obtained cycles [(Me3N)HMP(SitBuPh2)]2 (M = Al: 1, Ga: 2) were functionalized by substituting the amine donor with the N-heterocyclic carbenes IPr and BImY to obtain the compounds [(NHC)HMP(SitBuPh2)]2 (IPr/Al: 3, BImY/Al: 4, IPr/Ga: 5, BImY/Ga: 6). All mentioned compounds feature an unusual external Lewis base stabilization as well as hydridic metal bound hydrogen atoms.