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PrCl3, NdCl3, SmCl3, ErCl3, and LuCl3 react with three mole equivalents of [Li(tmeda)][CHPhSiMe3] (1), [Li(tmeda)][CHPhSiMe2tBu] (2), [Li(tmeda)][CHPhSiMe2Ph] (3), and [Li(tmeda)][CH(C6H3Me2-3,5)SiMe2tBu] (4) forming the ate complexes [Li(tmeda)2][Ln(CHPhSiMe3)3Cl] (Ln = Pr (5a), Nd (6a), Sm (7a)), [Li(tmeda)2][Ln(CHPhSiMe2tBu)3Cl] (Ln = Pr (5b), Nd (6b), Sm (7b)), [Li(tmeda)2][Pr(CHPhSiMe2Ph)3Cl] (5c), and [Li(tmeda)2][Ln(CH(C6H3Me2-3,5)SiMe2tBu)3Cl] (Ln = Er (8d), Lu (9d)). {[Li(tmeda)]2[Nd(CHPhSiMe3)Cl4]}2 (10) and {[Li(tmeda)][Nd(CHPhSiMe3)Cl3(THF)]}2 (11) crystallize from concentrated ethereal solutions of 6a after addition of pentane. 4 reacts with two equivalents of ErCl3 and LuCl3 yielding [Li(tmeda)]2(μ-Cl)3Ln(CHPhSiMe2tBu)2 (Ln = Er (12), Lu (13)). Compounds 7a,b, 9d, and 13 have been characterized by 1H and 9d and 13 also by 13C NMR spectroscopy, compounds 6b, 7a, 8d, 9d, 10, 11, 12, and 13 by X-ray structure analysis.

A method for the Pd-catalyzed carbonylation of aryl bromides has been developed using Xantphos as the ligand. This method is effective for the direct synthesis of Weinreb amides, primary and secondary benzamides, and methyl esters from the corresponding aryl bromides at atmospheric pressure. In addition, a putative catalytic intermediate, (Xanphos)Pd(Br)benzoyl, was prepared and an X-ray crystal structure was obtained revealing an unusual cis-coordination mode of Xantphos in this palladium-acyl complex.

The reactions of PhCH2SiMe3 (1), PhCH2SiMe2tBu (2), PhCH2SiMe2Ph (3), 3,5-Me2C6H3CH2SiMe3 (4), and 3,5-Me2C6H3CH2SiMe2tBu (5) with nBuLi in tetramethylethylenediamine (tmeda) afford the corresponding lithium complexes [Li(tmeda)][CHRSiMe2R′] (R, R′ = Ph, Me (6), Ph, tBu (7), Ph, Ph (8), 3,5-Me2C6H3, Me (9), and 3,5-Me2C6H3, tBu (10)), respectively. The new compounds 5, 7, 8, 9 and 10 have been characterized by 1H and 13C NMR spectroscopy, compounds 7, 8 and 9 also by X-ray structure analysis.

The reaction of LuCl3(THF)3 with 2 equiv of LiCH2SiMe3 and 1 equiv of KCHPh2 (1) affords Lu(CH2SiMe3)2(CHPh2)(THF)2 (2). X-ray structural analyses show the benzhydryl unit to be planar in 1, but bent in 2.

Lu(CH2SiMe3)3(THF)2 (2) decomposes slowly at room temperature with formation of Me4Si. In order to understand the mechanism of this elimination process, Lu(CH2SiMe3)3([D8]-THF)2 (1), Lu(CH2SiMe3)3(THF)(DME) (3), and Lu(CH2SiMe3)3(THF)(diglyme) (4) were prepared. The results of 1H NMR spectroscopic studies of the decomposition in solution exclude an α- as well as a β -H elimination mechanism and point towards a γ -H elimination. The molecular structure of 4 has been determined by single crystal X-ray diffraction.

SmCl3 reacts with Me3SiCH2Li in THF yielding Sm(CH2SiMe3)3(THF)3 (1). The single crystal X-ray structural analyses of 1, Er(CH2SiMe3)3(THF)2 (2), Yb(CH2SiMe3)3(THF)2 (3), and Lu(CH2SiMe3)3(THF)2 (4) show the Sm atom in a fac-octahedral coordination and the heavier lanthanides Er, Yb, and Lu trigonal bipyramidally coordinated with the three alkyl ligands in equatorial and two THF molecules in axial positions. Metallorganische Verbindungen der Lanthanoide. 157 [1] Die Molekulstruktur von Tris(trimethylsilylmethyl)samarium, -erbium, -ytterbium und -lutetium SmCl3 reagiert mit Me3SiCH2Li in THF unter Bildung von Sm(CH2SiMe3)3(THF)3 (1). Die Einkristall rontgenstrukturanalysen von 1, Er(CH2SiMe3)3(THF)2 (2), Yb(CH2SiMe3)3(THF)2 (3) und Lu(CH2SiMe3)3(THF)2 (4) zeigen das Sm Atom fac-oktaedrisch und die schweren Lanthanoide Er, Yb und Lu trigonal bipyramidal koordiniert mit den drei Alkylliganden in aquatorialer und zwei THF Molekulen in axialer Position.

The reaction of YbI2(THF)2 with diphenyldipyrrolylmethanide leads to a complex reaction from which an octameric divalent Yb macrocyclic complex, [diphenyldipyrromethanediyl-Yb]8, was obtained as a major product. A tetrameric cyclic Yb(II)-oxo complex, [(diphenyldipyrrolylmethanediyl)Yb]4[(K(THF)3]2(μ-O)·2(THF), arising from solvent deoxygenation and a monomeric Yb(III) complex, Yb(diphenyldipyrrolylmethanediyl)3[K(THF)]3, were also isolated as byproducts of a complex reaction.

The X-ray crystal structures of Hg(C6F4X-p)2 (X = NH2, OMe, or Me) show the compounds to have almost linear C–Hg–C stereochemistry (X = NH2, 176.3(4)°; X = OMe, 179.5(2)°; X = Me, 176.3(2)°), and the two tetrafluoroaryl rings rotated ca. 52–62° with respect to each other. Substantial conjugation of NH2 and OMe groups with the aromatic rings is evident from N–C and O–C(Ar) distances. For X = NH2 or OMe, two weak N(O)–Hg coordination interactions per mercury lead to a two dimensional supramolecular chain structure containing pairs of π-stacked aromatic rings at near van der Waals contact distances rotated at 62.2° (X = NH2) or 52.9° (X = OMe) to each other. In Hg(C6F4Me-p)2, which does not have potential donor atoms, no supramolecular structure is obtained, the molecules being laterally displaced from one another. Organoquecksilber-Verbindungen. 33 Die Kristallstrukturen von Hg(C6F4X-p)2 (X = NH2, OMe, Me) – Zwei Beispiele fur supramolekulare Lewis-Saure-Base-Komplexe In den Kristallstrukturen von Hg(C6F4X-p)2 (X = NH2, OMe, or Me) liegen nahezu lineare C–Hg–C-Gruppen vor (X = NH2, 176,3(4)°; X = OMe, 179,5(2)°; X = Me, 176,3(2)°); die beiden Tetrafluoroaryl-Ringe sind um 52–62° gegeneinander verdreht. Aus den Abstanden N–C und O–C(Ar) ergibt sich eine deutliche Konjugation der NH2- und OMe-Gruppen mit den aromatischen Ringen. Zwei schwache koordinative N(O)–Hg-Wechselwirkungen pro Hg-Atom ergeben fur X = NH2 bzw. OMe eine zweidimensionale supramolekulare Kettenstruktur aus Paaren von uber π-Wechselwirkungen gestapelten aromatischen Ringen mit nahezu van der Waals-Kontakten; die aromatischen Ringe sind um 62,2° (X = NH2) bzw. 52,9° (X = OMe) gegeneinander verdreht. Hg(C6F4Me-p)2 hat keine potentiellen Donor-Atome; folgerichtig wird keine supramolekulare Struktur beobachtet, die Molekule liegen seitwarts nebeneinander.

A method for the Pd-catalyzed carbonylation of aryl bromides has been developed using Xantphos as the ligand. This method is effective for the direct synthesis of Weinreb amides, 1° and 2° benzamides, and methyl esters from the corresponding aryl bromides at atmospheric pressure. In addition, a putative catalytic intermediate, (Xanphos)Pd(Br)benzoyl, was prepared and an X-ray crystal structure was obtained revealing an unusual cis-coordination mode of Xantphos in this palladium−acyl complex.

[reaction: see text] The direct transformation of aryl bromides into the corresponding Weinreb amides via Pd-catalyzed aminocarbonylation at atmospheric pressure is reported.

The structures of three adventitiously obtained peroxolanthanoid complexes have been determined, namely, [Yb2(Cp)4(μ-O)2/3(μ-O2)1/3(thf)2] (1) (Cp = cyclopentadienyl; thf = tetrahydrofuran), which has disorder between the bridging oxide and peroxide, [Nd2(o-PhPhForm)4(thf)4(μ-O2)] (2) (o-PhPhForm = N,N′-bis(2-phenylphenyl)formamidinate), and [Eu4(FForm)6(μ-OH)2(μ3-O2)2(μ-diglyme)2]·2diglyme (3) (FForm = N,N′-bis(2-fluorophenyl)formamidinate, diglyme = bis(2-methoxyethyl) ether). In the first two complexes, the peroxide bridges side-on between metals, whereas in the last complex, each peroxide bridges three metals through both oxygen atoms. The first complex was a single crystal amongst a bulk sample of [Yb(Cp)2(pzPh)(thf)] (pzPh = 2-(1′-pyrazolyl)phenyl), prepared by oxidation of dicyclopentadienylytterbium(ii) by bis(2-(1′-pyrazolyl)phenyl)mercury, the structure of which was also determined and showed distorted square planar stereochemistry for mercury.