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Hydrides of group

Metal hydrides of Groups 13 (IIIA) and 14 (IVA) of the periodic table (e.g., AIH3, GaH3) as well as many of their alkyl and aryl derivatives (e.g., R2AIH, Ar3SnH) add... [Pg.1016]

Further studies quickly revealed that the rapid dehydrogenative coupling of primary organosilanes to oligomers and the slower coupling of secondary silanes to dimers can be effected under ambient conditions with compounds of the type CP2MR2 (M = Ti, R = alkyl M = Zr, R = alkyl or H)(11,12,13). None of the other metallocenes, metallocene alkyls, or metallocene hydrides of groups 4, 5 or 6 have shown any measurable activity for polymerization... [Pg.91]

FIGURE 6.8 Boiling points of hydrides of groups IVA,VA, VIA, and VIIA. [Pg.196]

The boiling temperatures of the hydrides of group 6 are shown opposite. [Pg.39]

Figure 4.95 Vertical trends in geometry of saturated MH hydrides of group 4 (Ti,... Figure 4.95 Vertical trends in geometry of saturated MH hydrides of group 4 (Ti,...
Table 4.53. Comparison bond lengths 7 mh and angles O uafor saturated metal hydrides of groups 4, 6, and 10 (H and H" denote inequivalent short and long hydride bonds in MH6 compounds)... Table 4.53. Comparison bond lengths 7 mh and angles O uafor saturated metal hydrides of groups 4, 6, and 10 (H and H" denote inequivalent short and long hydride bonds in MH6 compounds)...
The catalyst component consists of halides of IV-VIII group elements having transition valence and the cocatalysts are organometallic compounds like alkyls, aryls and hydrides of group I-IV metals. Although there are hundreds of such catalyst cocatalyst systems listed in table below. Systems based on the organoaluminium compounds such as triethyl aluminium (AlEt3) or diethyl aluminium chloride... [Pg.265]

The minimum oxygen concentration for explosion of most volatile hydrides of Group IIIa-Va elements is nearly zero, so complete exclusion of air or oxygen is essential for safe working. Presence of impurities in hydride mixtures further increases the danger of ignition. [Pg.286]

You can see the effect of hydrogen bonding clearly in the boiling point data of the binary hydrides of Groups 14 to 17 (IVA to VIIA), shown in Figure 4.16. In Group 14, the trend in boiling point is as expected. [Pg.193]

HCl and HF [56] with increasing values in a range [0.10, 0.45] respectively a negative sign and large magnitudes are common to other hydrides of group 13, for which calculations yield values —8.207 for [96] and —3.370 for... [Pg.284]

Having set out the properties of tantalum and zirconium hydride toward C-H bond activation of alkanes we now describe the catalytic hydrogenolysis of C-C bonds. It was previously shown in the laboratory that supported-hydrides of group 4 metals, and particularly of zirconium, catalyze the hydrogenolysis of alkanes [21] and even polyethylene [5] into an ultimate composition of methane and ethane. However, to our initial surprise, these zirconium hydrides did not cleave ethane. (=SiO)2Ta-H also catalyzes the hydrogenolysis of acyclic alkanes such as propane, butane, isobutane and neopentane. But, unlike the group 4 metals, it can also cleave ethane [10], Figure 3.7 illustrates this difference of behavior between (=SiO)2Ta(H) and [(=SiO)(4.j,)Zr(H) ], x= or 2). With Ta, propane is completely transformed into methane by successive reactions, while with Zr only equimolar amounts of methane and ethane are obtained. [Pg.82]

Obviously, the alkane hydrogenolysis reaction highlights a clear difference in behavior between supported-hydrides of group 4 metals and (=SiO)2Ta(H),g (3) tantalum hydride. This difference in behavior can further be illustrated as follows ... [Pg.83]

TABLE 6.11. Experimental Interaction Energies Determined by IR Spectra for Dihydrogen-Bonded Complexes Eormed by Hydrides of Group 3A Elements ... [Pg.133]

This is the principal nomenclature system used in organic chemistry, as described in the Guide to lUPAC Nomenclature of Organic Compounds, p. 18. It is based upon the name of a formal parent molecule (normally a hydride), which is then substituted. Although it is principally an oiganic nomenclature, it has been extended to names of hydrides of Groups 14, 15, 16 and 17. [Pg.27]

A third method makes use of hydrides of group V elements together with volatile organometallic compounds of group III elements such as trimethylgallium and trimethylaluminium. [Pg.145]

That the molecules in solid and liquid water interact by hydrogen bonding and that hydrogen bonding is responsible for the anomalous properties of water compared with the other hydrides of Group 16... [Pg.1]

Boiling Points of the Covalent Binary Hydrides of Groups 4A, 5A, 6A, and 7A... [Pg.390]

Apart from the binary hydrides of Groups 16 and 17, Lowry/ Brpnsted acids in aqueous solution are nearly all oxoacids, i.e. substances containing O-H bonds which ionise in aqueous solution to give oxo-anions and H+(aq) (or H30+). Most oxoacids are molecular hydroxides E(OH) , such as B(OH)3, Ge(OH)4 and Te(OH)6, or oxohydroxides EOm(OH) . In addition, we have more complex species containing E-E bonds or E-O-E bridges. In EOm(OH) - for example, N02(0H), PO(OH)3, S02(0H)2,103(0H) - the m O atoms are held to E by bonds having at least some double bond character, via p -p or d -p overlap. Oxohydroxides may be seen as being derived from hydroxides by elimination of H20, and are favoured by elements E whose atoms form double bonds to O atoms. [Pg.329]

Ziegler-Natta catalysts are defined as the products formed in reactions of transition metal compounds of groups 4 to 8 (procatalysts, catalyst precursors) with organometallic compounds or metal hydrides of groups 1 to 4 (activators). These reactions are carried out in an inert medium and under inert (anaerobic) conditions ... [Pg.53]

In reporting a Ziegler-Natta catalyst, the kind of transition metal compound should not be omitted. Group 4-8 transition metal compounds, such as halides, oxyhalides, alkoxides, acetylacetonates, etc., have been used as catalyst precursors with activators such as alkyl derivatives or hydrides of group 1-4 metals. Titanium chlorides and triethylaluminium are most commonly applied for the preparation of heterogeneous catalysts in an aliphatic hydrocarbon medium. Also, vanadium oxychloride or acetylacetonate and dialkyaluminium chloride are often used for the preparation of homogeneous catalysts in an aliphatic hydrocarbon or an aromatic hydrocarbon medium. [Pg.54]

The apparent radius of the H- is determined from the M-H distance in the crystal by subtracting the known radius of M+. It is obvious from the data shown in Table 6.3 that the radius assigned to H in Li-H is smaller than in other hydrides of Group IA. The Li-H bond is considered to have a substantial amount of covalent character. Probably the greater covalency... [Pg.160]

Molten hydrides of Groups IA and IIA are good electrical conductors, and hydrogen is liberated at the anode as a result of the oxidation of IF ... [Pg.161]

Ziegler-Naita caialysts consist of a combination of alkyls or hydrides of Group I-III metals with salts of the Group IV-VHI metals. The most generally efficient catalyst combinations are those in which an aluminum alkyl derivative is interacted with titanium, vanadium, chromium or zirconium salts. The most important application of these catalysts is in the polymerization of olefins and conjugated dienes. Not every catalyst combination is equally effective in such polymerizations. As a general rule, Ziegler-Natta combinations that will polymerize 1-olefins will also polymerize ethylene, but the reverse is not true. [Pg.334]

Other Diatomic Hydrides of Group 6.—The absorption bands of the... [Pg.45]


See other pages where Hydrides of group is mentioned: [Pg.17]    [Pg.127]    [Pg.418]    [Pg.550]    [Pg.2]    [Pg.26]    [Pg.17]    [Pg.127]    [Pg.269]    [Pg.239]    [Pg.193]    [Pg.53]    [Pg.120]    [Pg.173]    [Pg.220]    [Pg.5]    [Pg.789]    [Pg.125]    [Pg.2432]    [Pg.1489]    [Pg.1489]    [Pg.750]    [Pg.766]    [Pg.213]   
See also in sourсe #XX -- [ Pg.499 , Pg.499 ]




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Addition of Group IVB hydrides to olefins

Group hydrides

Hydride Compounds of the Titanium and Vanadium Group Elements

Hydride Reduction of a Carbonyl Group

Hydrides of the Group IVA Elements

Hydrides of the Other Group 13 Metals Preliminaries and Prospects

Hydrogen Donor Abilities of the Group 14 Hydrides

Lewis base reaction of group 13 hydrides

OTHER HYDRIDES OF GROUP V ELEMENTS

Pre-Reduction of Carbonyl Groups with Lithium Aluminum Hydride

Reactivities of Group 14 Hydrides

Reduction of Other Functional Groups by Hydride Donors

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