Linear indium compounds

M. S. Hill, R B. Hitchcock and R. Pongtavornpinyo, A linear homocatenated compound containing six indium centers. Science 311, 1904-7 (2006). 

Table tr.1-78 Linear thermal expansion coefficient a of indium compounds... 

An important aspect of reliable susceptibility measurements is the calibration of the magnetometers with respect to field and temperature a number of high-purity compounds exist to calibrate (1) the applied field via measurement of the susceptibility (palladium metal, HgCo(NCS)4), (2) the temperature linearity via determination of the Curie constant of (NH4)2Mn(S04)2-6H20, or (3) the absolute values of the sample temperature that are especially important for low-temperature measurements and for which the critical temperatures of pure-element low-7 c superconductors can be used, for example, lead (7.20 K) or indium (3.41 K).11... 

Recently the first compounds containing Si=Ga or Si=In double bonds, l,3-disila-2-gallata- and -indataallenic anions respectively, were obtained in the form of lithium salts as dark red crystals by the reaction of bis(6i-tert-butylmethylsilyl)dihthiosilane, with the respective M(III) halide (Figure 18). " X-ray crystallographic analysis of galhum and indium salt derivatives showed that the > SiMSi< frameworks (M = Ga, In) are not linear and the two Si=M... 

Triorganogallium, indium and thallium compounds are air-and moisture-sensitive. Hydrolysis initially yields the linear [R2M]+ ion (which can be further hydrolysed), in contrast to the inertness of R3B towards water and the formation of A1(0H)3) from R3AI. The [R2T1J+ cation is also present in... 

The largest well-defined oligomer of this type is currently the linear hexa-indium complex, 21 (Fig. 8), supported by a single ortho- y y substituted P-diketiminate ligand at each four-coordinate In centre and terminated by two iodide substituents to maintain charge balance [200]. Compound 21 displayed an absorption maximum in hexane at ca. 349 nm, which was interpreted as evidence for the existence of electronic delocalisation across the indium a framework analogous to that observed in isoelectronic catenated group 14 systems. 

No monomeric alkali metal alkyls or aryls are known, as those crystal structures which have been determined indicate electron-deficient, e.g. (MeLi), or ionic (K Me ) constitutions. The dialkyls of the lighter second group metals are mostly electron-deficient dimers or polymers, but those of zinc, cadmium and mercury are monomers with a linear structure as expected from participation of one (metal) s and one p orbital (with or without dji participation). In the third group the pattern is more complex. Whereas the trialkylboranes are monomeric, boron hydrides (and alkyl hydrides) and polyboron compounds form electron-deficient structures. Aluminium alkyls and alkyl hydrides are normally electron-deficient dimers or trimers gallium trialkyls are monomeric though the trivinyl is a dimer trimethylindium is a weakly associated tetramer in the solid state, otherwise all indium and thallium trialkyls appear to be monomers. 

An interesting approach to imino sugars was presented by Behr and coworkers/ Using an indium-mediated allylation of a carbonyl group in the unprotected pentosylamines such as 194, they prepared the linear diene 195 with very high diastereoselectivity dr> 95 5 Scheme 40). The latter compound was then in situ protected with p-toluenesulfonic acid (as ammonium salt) and subjected to the RCM reaction with the Hoveyda-Grubbs II cat. which afforded derivative 196 with a long, poly-hydrojylated side-chain. 

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