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Eight dinuclear methyl aluminium(III) bis(amidinate) and bis(guanidinate) complexes have been synthesized in good to very good yields and were fully characterized by means of 1H, 13C, and IR spectroscopy as well as elemental analysis. Five of them were successfully converted to the respective dinuclear aluminium iodide complexes and a dinuclear aluminium chloride bis(amidinate) complex was directly accessed by deprotonation of the ligand using ethyl aluminium dichloride. The molecular solid-state structures of eleven complexes were obtained from X-ray diffraction analysis. Furthermore, the catalytic activity of the dinuclear methyl aluminium complexes 3 and 4 has been probed in the ring-opening polymerization of e-caprolactone and L-lactide and the results highlight the impact of the metal–metal separation and the ligands’ backbone on activity and selectivity.

Water-rich aluminium halide hydrate structures are not known in the literature. The highest known water content per Al atom is nine for the perchlorate and fluoride. The nonahydrate of aluminium bromide, stable pentadecahydrates of aluminium chloride, bromide and iodide, and a metastable heptadecahydrate of the iodide have now been crystallized from low-temperature solutions. The structures of these hydrates were determined and are discussed in terms of the development of cation hydration spheres. The pentadecahydrate of the chloride and bromide are isostructural. In AlI3·15H2O, half of the Al3+cations are surrounded by two complete hydration spheres, with six H2O in the primary and 12 in the secondary. For the heptadecahydrate of aluminium iodide, this hydration was found for every Al3+.

I-2 released from fuel in the event of a severe nuclear reactor accident has the ability to deposit on surfaces in the containment building. This study has focused on the reactions of I-2 with reactive metals available in the containment. The experiments have been performed under conditions similar to those in a boiling water reactor at an accident situation. Copper, zinc and aluminium showed extensive uptake of gaseous I-2 under humid conditions. Reaction rates were determined at 25, 50 and 70degreesC and could be used for quantifying the effect of reactions between gaseous I-2 and copper, zinc and aluminium. Experiments with the metals placed in water showed lower I-2 uptake. Zinc iodide and aluminium iodide rapidly dissolves in water and no uptake of I-2 on these surfaces could be verified. Copper iodide has low solubility and I-2 was adsorbed on the surface. Experiments performed with reactive metals and methyl iodide showed a minor uptake of methyl iodide on zinc and aluminium in the gas phase for temperatures up to 80degreesC. A continuous uptake of methyl iodide on copper was measured at 80degreesC.

An efficient one-pot, three-component coupling reaction for the synthesis of β-iodo-α-(hydroxyalkyl) acrylates has been developed. As the iodine source as well as the Lewis acid mediator, diethyl aluminium iodide undergoes a Michael-type addition with methyl propynoate to form an active β-iodo allenolate intermediate, which in turn attacks various aldehydes or ketones to afford β-iodo Baylis–Hillman adducts in excellent yields with high Z-selectivity.

A combination of aluminium iodide and acetic anhydride effectively converts a variety of azides to their corresponding acetamides in good to excellent yields without perturbing many active functionalities such as ether, ester, nitro etc.

The addition of aluminum iodide (AlI3) to a mixed electrolyte, consisting of propylene carbonate (PC) and dimethyl carbonate (DMC), containing lithium hexafluorophosphate (LiPF6), was found to reduce the charge–discharge cyclability of a Li metal electrode. In contrast, addition of magnesium iodide (MgI2) improved the Li cycling efficiency in the same electrolyte. The origin of the addition effects on the cyclability was investigated by electrochemical and chemical analyses; ac impedance and X-ray photoelectron spectroscopy revealed that the addition of MgI2 to the electrolyte provided a low-resistance interface on the Li anode while in the presence of AlI3 the decomposition products of PF6− at the Li interface impeded the charge–discharge cycling of Li.

The reactions of aluminium(III) iodide with a number of common potentially chelating ethers and esters have been studied in diethylether or carbon disulphide solutions. Cleavage of the O-C bond occurred under very mild conditions. Differences in reactivity of aluminium iodide towards some closely related compounds suggest chelation is important in the mechanism of cleavage.

Aluminium iodide, prepared from dry aluminium foil and iodine, in acetonitrile is shown to convert bicyclic ketals in the 6,8-dioxabicyclo[3.2.1]octane series into a cyclohexenone and a substituted pyridine in one step. Details of the structural analysis are discussed. The role of the 1,5-diketone as intermediate for the formation of the cyclohexenone and the pyridine from the bicyclic ketal was secured by subjecting the isolated diketone to various reaction conditions.

Reaction between diiodomethane, CH 2 I 2 , and an Al(111) surface has been studied by means of surface analytical techniquesunder ultrahigh vacuum. Thermal desorption experiments revealed that an alkyl-aluminum complex desorbed at 472 K as a dominant desorption species from the surface adsorbed by CH 2 I 2 to a coverage of less than l monalayer (ML). On the contrary, desorption of ethylene, physisorbed CH 2 I 2 , and aluminium iodide began to be observed obove l ML at 150 K and 190 K and around 380 K respectively

Cheap and environmentally benign electrochemical energy conversion and storage devices, including a dye-sensitized solar cell (DSSC) using an AlI3-ethanol electrolyte and a new Al/I2 primary battery, are reported. The AlI3-ethanol electrolyte can be prepared simply by adding aluminum powder and iodine into ethanol at ambient conditions. The DSSC using this AlI3-ethanol electrolyte achieved an energy conversion efficiency of 5.9% at AM 1.5 (100 mW/cm-2). In the Al/I2 battery, AlI3 is formed spontaneously when aluminum and iodine electrodes are brought into contact at room temperature. Then I- anions transport across the AlI3 solid electrolyte for further electrochemical reactions.

Aluminium iodide has been developed as an efficient reagent for the conversion of aldoxims to nitriles and the Beckmann rearrangement of ketoximes to anilides.

Aluminium iodide, prepared from dry aluminium foil and iodine, in acetonitrile is shown to convert bicyclic ketals in the 6,8-dioxabicyclo[3.2.1]octane series into a cyclohexenone and a substituted pyridine in one step. Details of the structural analysis are discussed. The role of the 1,5-diketone as intermediate for the formation of the cyclohexenone and the pyridine from the bicyclic ketal was secured by subjecting the isolated diketone to various reaction conditions.

Es wurde der Einflus einiger n-Alkylhalogenide (n-Butylfluorid, n-Butylchlorid und n-Butylbromid) und einiger Benzylhalogenide (Benzylfluorid, Benzylchlorid und Benzylbromid) auf die durch Aluminiumjodid katalysierte Polymerisation des Isobutylens in Heptan studiert. Dabei wurde festgestellt, das das n-Butylfluorid und die Benzylhalogenide die Polymerisationsgeschwindigkeit wesentlich erhohen. Aus der Abhangigkeit der Polymerisationsgeschwindigkeit und der Molekulargewichte der gewonnenen Polymeren von der Konzentration der Alkylhalogenide und des Aluminiumjodids geht hervor, das die Alkylhalogenide nicht als Cokatalysatoren wirken, sondern das die Erhohung der Polymerisationsgeschwindigkeit durch katalytisch aktive Produkte verursacht wird, die durch Halogenaustausch zwischen dem Aluminiumjodid und den Alkylhalogeniden gebildet werden. Die Ergebnisse der vorliegenden Arbeit werden im Zusammenhang mit den Erkenntnissen diskutiert, die uber die Polymerisation des Isobutylens mit den aus zwei FRIEDEL-CRAFTS-Halogeniden bestehenden Katalysatorsystemen gewonnen wurden. An investigation was made on the effect of some n-alkyl halides (n-butyl fluoride, n-butyl chloride, and n-butyl bromide) and some benzyl halides (benzyl fluoride, benzyl chloride, and benzyl bromide) on the polymerization of isobutene in heptane, catalyzed by aluminium iodide. It was found that n-butyl fluoride and benzyl halides raise the rate of polymerization considerably. It was also established, from the dependence of the rate of polymerization and of the molecular weights on the concentration of alkyl halides and aluminium iodide, that alkyl halides do not act as cocatalysts, but that the increase in the rate of polymerization is due to the formation of catalytically active products of halogen exchange between aluminium iodide and alkyl halides. The results are discussed in terms of our present knowledge concerning the polymerization of isobutene with catalytic systems consisting of two FRIEDEL-CRAFTS halides.

It is shown, that organic molecules for which a strong donor-acceptor interaction with aluminium triiodide can be expected, with formation of a molecular complex, cause a strong “exchange blocking” effect in the AlI3C2H5I liquid system. Independently of the amount of the added foreign compound, however, a significant part (about 20–30 per cent) of the radioiodine atoms primarily present in the metal iodide is transferred to the ethyl iodide in the first rapid period of the exchange. The suggest a significant role for intermediate compounds and/or solid-liquid surface exchange. Aromatic hydrocarbons and olefines which are supposed to form π-complexes with aluminium trihalides, cause no effect on the iodine exchange in the system investigated.

Phosphor(III)-jodid bildet mit Aluminiumjodid die Additionsverbindung 2 PJ3 · AIJ3, in der wahrscheinlich eine symmetrische trigonale Bipyramide (Symmetrie D3h) mit sp3d- Bindungshybridisierung und der Koordinationszahl 5 am Aluminium vorliegt. Die Bildung eines 1:1-Adduktes wurde unter den angegebenen Bedingungen nicht beobachtet. Diphosphor-tetrajodid erfahrt durch Aluminiumjodid eine teilweise Disproportionie-rung gemas der idealisierten Gleichung P2J4 (-PJ-) + PJ3. Es bildet ein hochpolymeres amorphes Reaktionsprodukt wechselnder Zusammensetzung mit einem P:J- Verhaltnis von etwa 1:1, das durchschnittlich 1 Al-Atom auf 5 P-Atome enthalt. Auserdem entsteht als Hauptprodukt die Additionsverbindung P2J4 · AlJ3, zusammen mit dem als Folge der Disproportionierung gebildeten 2 PJ3 · AlJ3 sowie einer kleinen Menge von P2J4 · 2 AlJ3. Bei beiden Phosphorjodiden ist in den Additionsverbindungen das Verhaltnis P:Al = 2:1 bevorzugt. Phosphorus(III)-iodide forms with aluminium iodide the addition compound 2 PI3 · AlI3 which has probably trigonal-bipyramidal structure (symmetry D3h) corresponding to sp3d- hybridization and the coordination number 5 of aluminium. The formation of an 1:1 adduct was not observed under the described conditions. Diphosphorus tetraiodide is partially disproportionated by aluminium iodide according to the (idealized) equation P2I4 (-PI-) + PI3 to yield a highpolymeric amorphous product with an approximate P:I ratio of unity and as an average a P:Al ratio of 5:1. Besides the addition compound P2I4 · AlI3 is formed as the main product of the reaction. Moreover, 2 PI3 · AlI3 arises as a result of the disproportionation and small amounts of P2I4 · 2 AlI3 are sometimes detectable. In the addition compounds of both of the phosphorus iodides the ratio of P:Al = 2:1 is preferred.

Mono- and di-iodomonomethylsilane, CH3SiH2I and CH3SiHI2, have been prepared by the reaction of monomethylsilane with hydrogen iodide in the presence of aluminium iodide. The monoiodo compound reacts with water to form the siloxan, (CH3SiH2)2O, with mercuric sulphide to form the silthian, (CH3SiH2)2S, and with silver cyanide to form the isocyanide, CH3SiH2NC, all of which have been characterised. The isocyanide does not react with nickel carbonyl and rapidly polymerises in the presence of boron trifluoride.

The polymerization of methyl linoleate in the presence of aluminium halides, AlI3, AlBr3, AlCl3 and AlF3 at 300°C was studied. The result shows that only aluminium iodide among the halides promotes the polymerization. The effects of reaction conditions on the polymerization of methyl linoleate with aluminium iodide were studied further. The main results obtained are as follows : (1) The increase of catalyst concentration at 300°C decreases the time required for the polymer content to reach 70%. (2) As the reaction temperature increased in the polymerization with 2mol% aluminium iodide in 250325°C, the amount of polymer formed was increased. (3) The maximum polymer content of the product under the following reaction condition was about 75%, catalyst concentration 2mol%, reaction temperature 325°C, and reaction time 10hr.The dimer separated from polymerization product with aluminium iodide was catalytically dehydro-genated. From the results of analyses of the dehydrogenated dimer and other information, it is considered that the polymerization of methyl linoleate with aluminium iodide catalyst involves mainly the Diels-Alder reaction.

The Al–Al2Br6and Al–Al2I6binary systems have been investigated by cryoscopy and solubility measurements. Pure Al2BrGmelts at 98.01 ± 0.02 °C; the eutectic is found at 97.91 ± 0.02 °C and 0.017 wt. % Al; at 254 °C the solubility of aluminium increases to 0.0195 wt. %. Pure Al2I6melts at 188.32 ± 0.02 °C; the eutectic is found at 188.17 ± 0.02 °C and 0.018 wt. % Al; at 320 °C the solubility increases to 0.021 wt. % Al. From the results it is concluded that dissolved aluminium is present in the melt either as Al20dimer species or as associated molecules of Al4Br6and Al4I6.

The 4-amino-benzophenone (L) complexes: 2BCl 3 ·3L, yellow, 3AlCl 3 ·L·6H 2 O, yellow, 2AlCl 3 ·L·6H 2 O, red, 4AlCl 3 ·L, yellow, AlBr 3 ·3L, yellow and red, 3AlBr 3 ·4L, yellow and red, AlI 3 ·4L, deep green, and AlI 3 ·L, black, have been prepared and investigated by i.r. spectroscopy. The ligand is H 2 N-coordinated in the BCl 3 , AlCl 3 and AlBr 3 complexes for which a CO-coordination is excluded. A ν(CO) frequency decrease indicates a CO interaction in the aluminium iodide complexes for which a H 2 N-coordination is excluded.

Obtention des phenols correspondants par desalkylation d'ethers aromatiques par l'iodure de Al(III) en presence d'iodure de tetrabutyl ammonium

I HAD two samples of aluminium iodide in two hermetically sealed glass tubes sent by a German firm. One of them was passing round the class, and the other was lying on the demonstration table. Suddenly a report was heard, and I found that he tube on the table had exploded, and its contents had been thrown out. Both the tubes were perfectly sound, and therefore there seems to be no reason to suspect that the volatile compound found an explosive mixture with the air. The temperature of the lecture room was at the time nearly 95° F. I communicate this matter to you to find out if others have had similar experience with aluminium iodide.

Aluminium iodide reduces sulphonyl chlorides to disulphides and sulphoxides to sulphides under mild conditions in acetonitrile.

Some fluoroamatic compounds have been photoisomerised to bicyclo[2,2,0]hexa-2,5-diene derivatives, which were re-aromatised on heating. Hexafluorobenzene gave hexafluorobicyclo[2,2,0]hexa-2,5-diene in good yield. This compound added bromine and hydrogen, and gave 2,5- and 2,6-disubstituted products on treatment with sodium ethoxide or methyl-lithium; phenylation afforded 1-fluoropentaphenyl- and 1,4-difluorotetraphenylbenzene; on treatment with aluminium chloride in methylene chloride and with aluminium iodide in methyl iodide, 1-chloropentafluoro-, 1,4-dichlorotetrafluoro-, and 1-iodopentafluoro-bicyclo[2,2,0]hexa-2,5-diene, respectively, were obtained. 2H-Pentafluorobicyclo[2,2,0]hexa-2,5-diene was obtained from pentafluorobenzene in low yield, and was also synthesised by a different route. Octafluorotoluene gave perfluoro-1- and -2-methylbicyclo-[2,2,0]hexa-2,5-diene. The former added bromine and hydrogen; the latter added bromine and hydrogen fluoride and could be dimerised. Decafluoro-p-xylene gave perfluoro-1,4- and -2,5-dimethylbicyclo[2,2,0]hexa-2,5-diene in low yield.

By use of solution reaction calorimetry, the standard enthalpies of formation of aluminium bromide and aluminium iodide have been determined as: ΔHf° AlBr3(cryst.)298·15 K =–494·8 ± 2·7 kJ mol–1(–118·3 ± 0·6 kcal mol–1); and ΔHf° All3(cryst.)298·15 K =–280·4 ± 2·6 kJ mol–1(–67·0 ± 0·6 kcal mol–1). Relevant thermodynamic parameters for the series (AlX3)n(X = F, Cl, Br, or I; n= 1 or 2) have been recalculated and are reported.

WE have recently investigated the reaction between monosilane, SiH1, and hydrogen iodide at 80° in the presenee of aluminium iodide, and have isolated from the products two stable iodides of the formulae SiH2I2 and SiH3I, which are formed together with silico-iodoform and silicon tetraiodide. The former is a heavy colourless liquid of low volatility (vapour pressure 2–3 mm. at 0°), while the monoiodide is a liquid of boiling point 45·8° and melting point—56·5°, which resembles methyl iodide in appearance.