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Darstellung, Eigenschaften und Spektren von cis-[Co(CN)3(NH3)3] werden beschrieben. Die Rontgenstrukturanalyse beweist die cis-Konfiguration. Bei der thermischen Zersetzung entstehen Co2(CN)5NH2 und Co2(CN)5. Mit Ag+ und Hg2+ werden Uberkomplexe gebildet. The preparation and properties of cis-[Co(CN)3(NH3)3] are described. The vibrational, ultraviolet and visible spectra have been measured. The structure of the compound has been determined by X-ray methods. By thermal decomposition of the compound, Co2(CN)5NH2 and Co2(CN)5 have been obtained. Supercomplexes are formed with Ag+ and Hg2+ ions.

Darstellung und Eigenschaften einer Reihe von Salzen mit dem bisher unbekannten Anion cis-[Co(SO3)2(CN)45− werden beschrieben. Die Darstellungsmethode fur trans-[Co(SO3)2(CN)4]5−-Salze wird verbessert, wobei auch das neue Salz K4[CoSO3(CN)5] · 4H2O erhalten wird. Die Konfiguration der isomeren cis- und trans-Disulfitotetracyanokobaltate(III) ergibt sich aus ihren Raman-, UR- und UV-Spektren. The preparation and the properties of a series of salts containing the new anion cis-[Co(SO3)2(CN)4]5− are described. The method of preparation of the trans[Co(SO3)2 · (CN)45− complex is improved and the new salt K4[CoSO3(CN)5] · 4H2O is described. The configuration of the cis- and trans-[Co(SO3)2(CN)4]5− complexes results from their Raman, IR and UV spectra.

This section comprises all compounds in which the 1L ligand is connected to the iron atom with a single bond and contains a positive charge at any position of the ligand. Compounds with the 5L ligand other than C5H5, i.e., with the Cp*Fe(CO)2 group (Fp*) instead of C5H5Fe(CO)2 (Fp*), are restricted to a few species and added at the end of the appropriate subsection.

This compound is formed by decomposition of K[Ga(CH3)2(GeH3)Cl]-1.5CH3OCH2CH2OCH3 (see p. 418) in C6H5CH3 at -15°C over a period of 2 h. Removal of KCl and solvent (pumping at -15°C for 2 d), followed by distillation at 25 to 30°C under high vacuum, yielded a colorless liquid consisting of a mixture of the compound (76%) and Ga(CH3)2H (based on analyses). The products could not be separated because Ga(CH3)2GeH3 decomposes slowly at 25°C to give Ga(CH3)2H and (GeH2)n.

The compound was first prepared by treating Ga(CH3)3 repeatedly with B2H6 at — 45°C until no further reaction was apparent [1]. In a more recent paper, Ga(CH3)3 was allowed to react with a fivefold excess of B2H6 at -15°C for 3 h and was isolated in a 20 to 42% yield by trap-to-trap distillation of the volatiles in a vacuum system [6]. An 80% yield was obtained from the reaction of Ga(CH3)2Cl with an excess of powdered LiBH4 at -15°C with pumping for 4 h and vacuum fractionation as above. This method was suitable for the preparation of Ga(CH 3 ) 2 BD 4 using LiBD4 [6]. The formation from GaH(BH4)2 and Ga(CH3)3 at -45°C, along with GaH(CH3)BH4, is indicated in a reaction scheme in [5].

This section deals with the unsaturated 17-electron species [5LFe(CO)2]. and the cationic 16-electron species [5LFe(CO)2]+. The short-lived radicals could only be characterized in some cases using a UV flash/IR monitoring apparatus.

Ga(CH3)2OH can be obtained by distilling Ga(CH3)3-O(C2H5)2 in a vacuum line onto a slight excess of H2O at -196°C and warming the mixture until hydrolysis is proceeding slowly. The rate of reaction can be regulated by controlling the temperature [2]. A checked version of this procedure with an 80% yield, starting with the in situ preparation of the etherate from GaCl3 and LiCH3 in ether at -78°C, is published in [8]. The resulting reaction mixture is allowed to stand at room temperature for 30 min, recooled to -78°C and hydrolyzed by dropwise addition of H2O. The workup involves dissolution of LiCl with H2O at room temperature, separation of the organic phase, evaporation of the solvent in an N2 stream, and recrystallization from petroleum ether [2,8]. The compound is also formed when either tetrameric Ga(CH3)2CN [5] or dimeric Ga(CH3)2P(C6H5)2 [6] is exposed to atmospheric moisture. The electroreduction of CH3I on a Ga cathode in CH3CN-NaClO4 gives the compound in about 35 to 40% yield along with “GaCH3O” [10]. The formation of Ga(CH3)2OH by thermal decomposition of Ga(CH3)2OOCH3 at 120°C in C9H20 [12] and of Ga(CH3)2OOC4H9-t under similar conditions [12,13] is also reported; see pp. 199/200.

[C5H5Fe]+C6H5CO0- forms in solution by photolysis (λ=359 and 466 nm) of benzoylferrocene and an excess of water in (CH3)2S0, pyridine, or dimethylformamide. The 1H NMR spectrum of a C5D5N solution shows a C5H5 resonance at δ=3.8 ppm along with signals of C6H5C00- and cyclopentadiene. Characteristic IR absorptions indicate the presence of a carboxylate group. Admission of oxygen produces a purple solution (λmax=550 nm), which displays the ESR spectrum of high-spin FeIII. Benzoic acid was isolated after acidification [1].

This chapter contains transition metal (M) compounds with Ga-M bonds. Other organogal-lium derivatives of transition metals without such a bond are described in Sections 13.6.2.1 to 13.6.2.4. With organogallium species five types of complexes have been described in the literature. Formula I represents adducts of Ga(C6H5)3 with anionic 18-electron complexes (no adducts with neutral species are known). Compounds with a three-coordinate Ga atom are described with Formulas II and III; the latter complexes have only been identified in solution. Compounds with a four-membered M-Ga-M-Ga ring (Formula IV) are only known as iron carbonyl derivatives and contain one molecule of a base at each Ga atom for stabilization. The base-free derivative of IV (No. 11 in Table 73) was also described but only characterized by IR spectroscopy. Incorporation of N-bases (C5H5N, tetramethylethylenediamine, 2,2′-bipyridyl) causes the molecule to monomerize to give compounds of Formula V, containing a formally “subvalent” Ga atom.

The compounds in this section, listed in Table 71, are of the GaR2ER2’ type (E = P or As, R’ = H only for No. 7), except for No. 6, which contains a Ga(CH3)Cl unit.

In this section 17-electron compounds of the type [5LFe(CO)2 1L]·+ and 19-electron compounds of the type [5LFe(CO)2 1L]·- are described in which the 5L ligands are represented by unsubstituted or substituted cyclopentadienyl groups. In general, the 17-electron systems (II) were obtained as short-lived intermediates by electrochemical oxidation of the corresponding neutral 5LFe(CO)2R complexes such as I which, in the presence of a donor molecule, result in the formation of highly reactive acyl complexes of the type [5LFe(CO)(2D)COR]·+ (e.g. III, IV) [5]. The 19-electron species were intermediates in the reduction-assisted migratory insertion [3, 6]. Mechanistic considerations based on the application of the configuration mixing (CM) model to the migratory insertion, assisted by either prior oxidation or reduction are given [6].

All compounds with Ga-S a bonds are listed in Table 48. They are mainly thiolates, GaR2SR’, most of them only recently prepared [12, 13]. The other derivatives contain potentially chelating ligands (Nos. 7 to 12 and No. 22), including chelating S N systems where it is impossible to distinguish between covalent and coordinative bonds to either the S or N atom. Derivatives of monothiocarboxylic acids, GaR2OC(S)R’. have already been described with the gallium-oxygen compounds in 5.1.3.2, p. 194. A few adducts are listed at the end of Table 48.

In this section, anionic compounds of mainly the type [C5H5Fe(CO)2 1L]- are collected in which the 1L ligand contains a negative charge. With exception of the first complex, which bears a deprotonated carboxylic group (Fp-substituted acetic acid), the salts are derived by formal addition of Fp- to CH2=C=O (I), CO2 (II, E=O), and CS2 (II, E=S). Two complexes containing C5H4CH3 and C5(CH3)5 as the 5L ligands are described at the end of the section.

The compounds in this section are arranged in a way similar to that of the previous sections, i.e., the description begins with tetraorganylgallates, [GaR4]-, and is followed by [GaRnX4-n]- anions (n = 1 to 3) where X stands for hydrogen, halogen, pseudohalogen, oxygen groups, etc. Finally, very extended subsections deal with organogallium pyrazolyl anions bonded to transition metal fragments via the second N atom of pyrazolyl, thus acting as anionic donor ligand with respect to the transition metal. Depending on the type of the transition metal moiety, these compounds may be neutral or ionic.

The present volume describes all organogallium compounds, i.e., compounds containing at least one gallium-carbon bond. It covers the literature completely.to the end of 1984 and includes many references to the literature up to the end of 1985. The organic chemistry of gallium is largely dominated by compounds of the types GaR3 (Chapter 1), GaR X _ (Chapters 2 to 12), and M[GaRnX4_nl (M = cation, Chapter 13), where X n 3 n stands for a non-carbon atom or any organic or organometallic group bonded to gallium through a non-carbon atom. The arrangement of GaR X - and M[GaRnX"_nlcompounds by n 3 n the kind of Ga-X bond is evident from the table of contents on pp. XI to XIV. The extensive use of pyrazolyl-containing organogallium anions as polydentate donor ligands in transition metal compounds resulted in a particularly voluminous chapter on anions with Ga-N bonds (13.6). The volume is concluded by a few low-valence organogallium compounds (Chapter 14) that (I) atom and an aromatic ligand in an TJe fashion. exhibit bonding interaction between a gallium Due to a free coordination site at the Ga atom, neutral compounds form many adducts with Lewis bases (symbol D). These adducts are described along with the parent substances either in a subsection of the respective chapter or in a common table at the end of the table.

The section collects all compounds derived from C5H5Fe(CO)2R in which the C5H5 ligand (Cp) is replaced by substituted Cp ligands (Cp*) or by other 5L ligands. The compounds are arranged as follows: C5H4R’ compounds (see Section 1.5.2.3.17.1) C5H3R’2, C5H2R’3, C5HR’4 or C5R’5 compounds (see Section 1.5.2.3.17.2) other 5L ligands (see Section 1.5.2.3.17.3)

Die Titelverbindung (II) wird als 1/3-Hydrat aus dem cis-Sulfitocyanocobaltat (I) durch Eindampfen mit Konigswasser, Abrauchen mit HCl, Auflosen des Produktes in konz. Ammoniak und Erhitzen im Autoklaven dargestellt (Raman-, IR-, Elektronenspektrum, Kristallstruktur).