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Digallane (dpp-bian)Ga—Ga(dpp-bian) (1) (dpp-bian is the 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) catalyzes the addition of 4-chloroaniline to some terminal alkynes RC≡CH (R = Bun, Ph, 4-MeC6H4). The reaction orders in each of the substrates were found for the reaction of phenylacetylene with 4-chloroaniline catalyzed by compound 1. The reaction of compound 1 with phenylacetylene in a molar ratio of 1: 10 led to 1-[N-(2,6-diisopropylphenyl)imino]-2-(1-phenylethylidene)acenaphthene (5) and the compound [C12H6(NC6H3Pr2 i)(PhC=CH2)(PhC=CH)]Ga(C≡CPh)2 (6). The reaction of digallane 1 with phenylacetylene and aniline in a stoichiometric ratio of 1: 2: 2 gave bis-anilide (dpp-bian)-Ga[N(H)Ph]2 (7) in 40% yield. The compound (PhC≡C)3Ga·THF (9) was obtained by the reaction of three equivalents of sodium phenylacetylide (prepared in situ from phenylacetylene and sodium) with one equivalent of GaCl3 in tetrahydrofuran. Compounds 5—7 and 9 were characterized by IR spectroscopy, 1H NMR spectroscopy was used to characterize products 5, 6, and 9, whereas EPR spectroscopy was used for amide 7. The structures of compounds 5—7 and 9 were determined by single crystal X-ray diffraction analysis.

Reduction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (1, dpp-bian) in the presence of SiCl4 with two equivalents of potassium graphite (KC8) in tetrahydrofuran leads to the formation of compound (dpp-bian)SiCl2 (2), which was also synthesized by the exchange reaction of SiCl4 with the magnesium complex (dpp-bian)Mg(THF)3. An analog of compound 2, the bromo derivative (dpp-bian)SiBr2 (3), was obtained by the reaction of SiBr4 with one equivalent of Na2(dpp-bian) (in situ from Na and dpp-bian) in toluene. The silylene (dpp-bian)Si (4) was synthesized by the reduction of a mixture of dpp-bian and SiCl4 (1: 1) with four equivalents of potassium graphite in tetrahydrofuran. Treatment of compound 4 with diimine 1 gives the derivative (dpp-bian)2Si (5). Compounds 2–5 were characterized by 1H, 13C, and 29Si NMR spectroscopy, as well as by elemental analysis, their molecular structure was established by X-ray diffraction studies.

The reactions of iron diiodide with one and two equivalents of the monopotassium salt of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-BIAN) in diethyl ether gave the complexes [(dpp-BIAN)FeI]2 (1) and (dpp-BIAN)2Fe (2), respectively. The bis-ligand complex (tms-BIAN)2Fe (3) was synthesized by the exchange reaction of the monosodium salt of 1,2-bis(trimethylsilylimino)acenaphthene (tms-BIAN) with iron diiodide. The reaction of FeI2 with tms-BIAN affords the chelate complex (tms-BIAN)FeI2 (4), whereas the reaction of FeBr2·2H2O with tms-BIAN is accompanied by elimination of trimethylsilyl groups to form the tris-ligand acenaphthene-1,2-diimine complex [(H2BIAN)3Fe][FeBr3·THF]2 (5) containing two types of iron ions. Compounds 1–5 were characterized by IR spectroscopy and elemental analysis. The molecular structures of 1–5 were determined by single-crystal X-ray diffraction. For high-spin complexes 1–3, the temperature-dependent magnetic susceptibilities were measured in the range of 4–300 K.

The reduction of 1,2-bis(trimethylsilylimino)acenaphthene and 1,2-bis{[3,5-bis(trifluoromethylphenyl)]imino}acenaphthene with metals gave magnesium, calcium, europium, zinc, and gallium complexes containing radical-anion and dianionic ligands of the 1,2-diiminoacenaphthene type. Their structures were studied by 1H NMR, ESR, and/or single-crystal X-ray analysis. Some chemical transformations of the complexes were carried out.

The reduction of 1,2-bis(trimethylsilylimino)acenaphthene (tms-BIAN, 1) with metallic lithium in toluene affords the dilithium salt (tms-BIAN)Li2· 1,3,2-Diazasiloles (tms-BIAN)SiCl2 (2) and (tms-BIAN)SiMe2 (3) were prepared by the reactions of (tms-BIAN)Li2 with SiCl4 and Me2SiCl2, respectively. The reaction of (tms-BIAN)Li2 with an excess of Me2SiCl2 produces (Cldms-BIAN)SiMe2 (4), where Cldms-BIAN is 1,2-bis(chlorodimethylsilylimino)-acenaphthene. The compound (tms-BIAN)(SiCl3)2 (5) containing two different silyl substituents (Me3Si and Cl3Si) at each nitrogen atom was synthesized by the reaction of compound 1 with Cl3SiSiCl3. The elimination of SiCl4 from compound 5 is accompanied by cyclization to give derivative 2. Compounds 2-5 were characterized by 1H, 13C, and 29Si NMR spectroscopy. The crystal structures of 2-5 were established by X-ray diffraction.

Oxidation of N,N′-bis(2,6-diisopropylphenyl)acenaphthylene-1,2-diamine (dpp-BIAN)H2 with silicon tetrachloride or mercury(II) chloride affords the [(dpp-BIAN)H2]·+[Cl]− compound. The corresponding iodine derivative, [(dpp-BIAN)H2]·+[I]−, was prepared by hydrolysis of the reaction products of the magnesium complex (dpp-BIAN)Mg(THF)3 with tetraiodosilane. X-ray diffraction study demonstrated that the [(dpp-BIAN)H2]·+ radical cation in these compounds chelates the corresponding halide anion.

Reactions of diimines dtb-BIAN and dph-BIAN with GeCl2 afford germanium(II) complexes with radical-anionic ligands, (dtb-BIAN)GeCl (5) and (dph-BIAN)GeCl (6a), respectively, where dtb-BIAN is 1,2-bis[(2,5-di-tert-butylphenyl)imino]acenaphthene and dph-BIAN is 1,2-bis[(2-biphenyl)imino]acenaphthene. The latter reaction gives 6a along with [(dph-BIAN)GeCl]+[GeCl3]− (6b). The reactions of tin(II) and antimony(III) chlorides with dtb-BIAN and dpp-BIAN produce complexes of these halides with neutral coordinated diimines, viz., (dtb-BIAN)SnCl2 (7) and (dpp-BIAN)SbCl3 (8) (dpp-BIAN is 1,2-bis[(2,6-di-isopropylphenyl)imino]acenaphthene). Paramagnetic complexes 5 and 6a were studied by ESR spectroscopy. Diamagnetic compounds 7 and 8 were characterized by 1H NMR spectroscopy. The structures of complexes 5, 6a,b, 7, 8, and (dpp-BIAN)Ge (9) were established by X-ray diffraction analysis.

The germanium(II) compound (dpp-BIAN)GeCl (1), which contains the radical anion of dpp-BIAN can be prepared either by reacting free dpp-BIAN ligand with 2 equiv of GeCl2(1,4-dioxane) in Et2O or by metathetical reaction of the sodium salt of dpp-BIAN with germanium dichloride in Et2O or benzene. The reaction of benzene solutions of 1 with 2 or 3 equiv of HCl led to protonation of the dpp-BIAN ligand affording [(dpp-BIAN)(H)2]•+[GeCl3]- (2) and [{(dpp-BIAN)(H)2•+}2(Cl-)]+[GeCl3]- (3), which incorporate the radical cation of the protonated ligand. Compounds 1−3 have been characterized by elemental analysis, IR, UV−vis, and electron spin resonance (ESR) spectroscopy. Molecular structures of 1−3 were determined by single-crystal X-ray diffraction. In molecule 1, the Ge atom is positioned at the apex of the slightly distorted trigonal pyramid. The Ge−N bond lengths in 1 are 2.0058(19) and 2.004(2) A. The molecular structure of 2 consists of contact ions [(dpp-BIAN)(H)2]+ and [GeCl3]-. In the molecular structure...

Metal exchange reactions of the magnesium complexes (dpp-BIAN)Mg(THF)n, (dtb-BIAN)Mg(THF)n, and (bph-BIAN)Mg(THF)n with GeCl2(dioxane) afford the stable germylenes (dpp-BIAN)Ge (1), (dtb-BIAN)Ge(Et2O) (2), and (bph-BIAN)Ge (3), respectively (dpp-BIAN = 1,2-[(2,6-iPr2C6H3)N]2C12H6, dtb-BIAN = 1,2-[(2,5-tBu2C6H3)N]2C12H6, bph-BIAN = 1,2-[(2-PhC6H4)N]2C12H6). Compound 1 is also obtained from (dpp-BIAN)Na4 and GeCl4 in Et2O. The germylenes 1−3 were characterized by elemental analyses, 1H NMR, 13C NMR, and IR spectroscopy, and X-ray crystal structure analyses. In the monomeric molecules the two imino nitrogen atoms coordinate the germanium atom. The aryl(N) groups are arranged rather orthogonal to the acenaphthenediimine plane. Compound 3 shows an anti geometry with the ortho phenyl substituents of both N-phenyl rings positioned on opposite sides of the acenaphthenediimine plane. The bite angles N−Ge−N are 85.2° (1) and 85.0° (3), respectively. The Ge−N bond distances in 1−3 range from 1.878 to 1.915 A.

The new rigid bidentate nitrogen ligands 1, 2-bis[(2, 5-di-tert-butylphenyl)imino]acenaphthene (1) (dtb-BIAN) and 1, 2-bis[(2-biphenyl)imino]acenaphthene (2) (bph-BIAN) have been synthesized by condensation of 1, 2-acenaphthylenedione with 2, 5-di-tert-butylaniline and 2-aminobiphenyl, respectively. Reduction of 1 and 2 with magnesium and calcium results in the formation of the monomeric metal complexes [(dtb-BIAN)Mg(THF)2] (3), [(bph-BIAN)Mg(DME)2] (4), and [(bph-BIAN)Ca(THF)3] (5). Compounds 1 — 5 have been characterized by C/H analyses, IR, 1H NMR, and 13C NMR spectra, the structures of 2, 3, and 5 have been estimated by single crystal X-ray diffraction. Monomere Magnesium- und Calciumkomplexe mit 1, 2-Bis[(2, 5-di-tert-butylphenyl)imino]acenaphthen (dtb-BIAN) und 1, 2-Bis[(2-biphenyl)imino]acenaphthen (bph-BIAN) als starre, dianionische Liganden Die neuen, starren und zweizahnigen Stickstoffliganden 1, 2-Bis[(2, 5-di-tert-butylphenyl)imino]acenaphthen (1) (dtb-BIAN) und 1, 2-Bis[(2-biphenyl)imino]acenaphthen (2) (bph-BIAN) werden durch Kondensation von 1, 2-Acenaphthylendion mit 2, 5-Di-tert-butylanilin bzw. 2-Aminobiphenyl erhalten. Die Reduktion von 1 und 2 mit Magnesium oder Calcium verlauft unter Bildung der monomeren Erdalkalimetallkomplexe [(dtb-BIAN)Mg(THF)2] (3), [(bph-BIAN)Mg(DME)2] (4) und [(bph-BIAN)Ca(THF)3] (5). Die Verbindungen 1 — 5 wurden durch C/H-Analysen, IR-, 1H-NMR- und 13C-NMR-Spektren, die Verbindungen 2, 3 und 5 daruberhinaus durch Rontgenstrukturanalysen charakterisiert.

The rate and pathway of reactions of 3,5-di-tert-butylbenzoyl trifluoroacetate with tert-butylphenols depend on the number and position of bulky substituents determining the extent of steric shielding of the phenolic hydroxyl.

1,2-Bis[(trimethylsilyl)imino]acenaphthene (1) was synthesized by the reaction of acenaphthenequinone with (Me3Si)2NLi in toluene followed by treatment of the reaction product with trimethylchlorosilane. The dianionic derivative [(tms-BIAN)Li2]2 (3) was obtained as the final product by reduction of compound 1 with lithium in toluene, whereas reduction in diethyl ether afforded the tetraanion [(tms-BIAN)Li4(Et2O)3]2 (5). The formation of the paramagnetic mono-and trianions in solution was confirmed by ESR spectroscopy. Compounds 3 and 5 were isolated in the crystalline state and characterized by elemental analysis, IR spectroscopy, and NMR spectroscopy. The crystal structures of 1, 3, and 5 were established by X-ray diffraction.