A series of low-coordinate tin and lead cationic complexes have been synthesized using the bulky β-diketiminate ligand [{N(2,6- i Pr2C6H3)C(Me)}2CH]− (BDI) to stabilize the metal center. Two different routes to [(BDI)Sn]+[X]− and [(BDI)Pb]+[X]− were explored (X = B(C6F5)4, AlCl4, MeB(C6F5)3): abstraction of the chloride with a Lewis acid from (BDI)SnCl and (BDI)PbCl and abstraction of a methyl group with a borane from (BDI)SnMe and (BDI)PbMe. The crystal structures of the tin and lead cations were determined; in both, solvent molecules were found to coordinate to the metal center. In the case of [(BDI)Pb]+[B(C6F5)4]−, a dichloromethane molecule was found. Density functional theory (DFT) calculations showed that this could be due to crystal packing. In the case of [(BDI)Sn]+[MeB(C6F5)3]−, an ether molecule was coordinated to the tin metal center. DFT calculations revealed a significant energy gain for the coordinated ether as opposed to the free molecules.

The reaction of isophthaloyl chloride and methyl-bis(trimethylsilyl)phosphane under mild conditions affords high yields of m-{-C(O)-C(6)H(4)(C(O)PMe)}(2) (1,10-dimethyl-1,10-diphospha-[3.3]-metacyclophane-2,9,11,18-tetraone): the first example of a diphosphametacyclophane.

Aroylphosphanes: base-free synthesis and their coordination chemistry with platinum-group metals

No abstract

The group 14 chloropropargyls R3EC ≡ CCH2Cl (R3E = (n)Bu3Sn, Ph3Sn, Me2PhSi, (i)Pr3Si, (n)Pr3Si, (n)Bu3Si), obtained by a modified literature procedure, react with LiPPh2 to afford the novel propargyl phosphanes Ph2PCH2C ≡ CER3 in high yield, as viscous oils; (Me3Si)2PCH2C ≡ CSiPhMe2 is similarly obtained from LiP(SiMe3)2. In contrast, the reaction of PhC[triple bond, length as m-dash]CCH2MgCl with ClP(NEt2)2 fails to produce a comparable propargyl phosphane, but generates preferentially (>70%) the novel phosphinoallene (Et2N)2PC(Ph) = C = CH2, which is characterised spectroscopically, and through its reaction with HCl. The coordination chemistry of representative phosphanes is explored with respect to platinum and palladium for the first time.

No abstract

Die Phenylendiamine (I) reagieren mit dem dibromierten Xylol (II) in siedendem Toluol in 59‐73%iger Ausbeute zu den tosylierten Dibenzodiazocinen (III), deren Hydrolyse mit HBr/Eisessig je nach Reaktionsdauer zu den freien Basen (IV) oder zu einem Gemisch aus freien Basen (IV) und den monotosylierten Derivaten (V) führt.

No abstract