Alanes structure

Recently, when attempting to isolate Eta Si-0-AIH2, we have discovered a new compound and a new type of siloxy alane structure. The siloxy alane Et3Si-0-AlH2 crystallizes as an adduct [EtsSi-O-A1H2]4 AI2H6, the structure of which is shown in Eig. 5 [17]. The compound is polymeric... 

GR Marshall, CD Barry, HE Bosshard, RA Dammkoehler, DA Dunn. The conformational parameter m drug design The active analog approach. ACS Symp Ser 112 205-226, 1979. JL Fauchere, ed. QSAR Quantitative Structure-Activity Relationships m Drug Design. New York Alan R Liss, 1989, pp 177-181. 

Recently Alan Fersht, Cambridge University, has developed a protein engineering procedure for such studies. The technique is based on investigation of the effects on the energetics of folding of single-site mutations in a protein of known structure. For example, if minimal mutations such as Ala to Gly in the solvent-exposed face of an a helix, destabilize both an intermediate state and the native state, as well as the transition state between them, it is likely that the helix is already fully formed in the intermediate state. If on the other hand the mutations destabilize the native state but do not affect the energy of the intermediate or transition states at all, it is likely that the helix is not formed until after the transition state. 

The publication of this paper led to a stampede of research, both experimental and theoretical, and an examination of earlier studies by eminent people like Roger Penrose and Alan Mackay in England about the possibilities of filling space by tiling with two distinct populations of tiles, as illustrated in Figure 10.8. This is the basis of quasicrystalline structure. 

As we saw in Chapter 3, the founding text of modern materials science was Frederick Seitz s The Modern Theory of Solids (1940) an updated version of this, also very influential in its day, was Charles Wert and Robb Thomson s Physies of Solids (1964). Alan Cottrell s Theoretical Structural Metallurgy appeared in 1948 (see Chapter 5) although devoted to metals, this book was in many ways a true precursor of materials science texts. Richard Weiss brought out Solid State Physics for Metallurgists in 1963. Several books such as Properties of Matter (1970), by Mendoza and Flowers, were on the borders of physics and materials science. Another key precursor book, still cited today, was Darken and Gurry s book. Physical Chemistry of Metals (1953), followed by Swalin s Thermodynamics of Solids. 

Niobium, tris(diethyldilhiocarbamato)oxy-stereochemistry, 1,82 structure, 1, 83 Niobium, tris(oxa ato)oxy-stereochcmistry, 1, 82 Niobium, tris(phcnylcncdirhio)-structure, 1, 63 Niobium alanate, 3, 685 Niobium complexes alkyl alkoxy reactions, 2, 358 amides, 2,164 properties, 2, 168 synthesis, 2, 165 applications, 6,1014 carbamicacid, 2, 450 clusters, 3, 672,673,675 hexamethylbenzene ligands, 3, 669 cyanides synthesis, 2, 9 p-dinitrogen, 3, 418 fluoro... 

The phosphinimide phosphanes 42 [75b], which are similar to the acyclic diphosphazanes comprising of one nitrogen and phosphorus atom, when treated with AlMea, (Scheme 19), were found to coordinate to the P(III) center to yield the alane adducts 43 which were characterized by the P-NMR spectroscopy and structure elucidation of 43a. 

Roberts, E (1986) GABA the road to neurotransmitter status. In BenzodiazepinejGABA receptors and chloride channels structural and functional properties (Eds Olsen, R and Venter, CJ), Alan R. Liss, New York, pp. 1-39. 

Bis(diamino)alanes (R2N)2A1H were used for the hydroalumination of terminal and internal alkenes [18, 19]. TiCb and CpjTiCb are suitable catalysts for these reactions, whereas CpjZrCb exhibits low catalytic activity. The hydroaluminations are carried out in benzene or THF soluhon at elevated temperatures (60°C). Internal linear cis- and trans-alkenes are converted into n-alkylalanes via an isomerization process. Cycloalkenes give only moderate yields tri- and tetrasubstituted double bonds are inert. Hydroaluminahon of conjugated dienes like butadiene and 1,3-hexa-diene proceeds with only poor selechvity. The structure of the hydroaluminahon product of 1,5-hexadiene depends on the solvent used. While in benzene cyclization is observed, the reaction carried out in THF yields linear products (Scheme 2-10). 

Jackson, M. J. Tai, C.-Y., Morphological correlates of weak electrolyte transport in the small intestine, in Dinno, M. A. (ed.), Structure and Function in Epithelia and Membrane Biophysics, Alan R. Liss, New York, 1981, pp. 83-96. 

ALAN M. RUSSELL and KOK LOONG LEE Structure-Property Relations in Nonferrous Metals... 

The reaction between a Lewis acid R3M and a Lewis base ER3 is of fundamental interest in main group chemistry. Synthetic and computational chemists have investigated the influence of both the Lewis acid and the base on the solid state structure and the thermodynamic stability of the corresponding adduct, that is usually expressed in terms of the dissociation enthalpy De. This led to a sophisticated understanding of the nature of dative bonding interactions. In particular, reactions of boranes, alanes and gallanes MR3 with amines and phosphines ER3, typically leading to adducts of the type R3M <— ER3, have been studied.10... 

Structural Trends within Alane and Gallane Adducts... 

H3A1 NMe3,53 whose structure has been determined by X-ray diffraction.54 Since these initial studies, comparable reactions were observed for alanes, gallanes and indanes R3M (M = Al, Ga, In R = H, halogen) with amines and phosphines, yielding bis-amine, bis-phosphine and mixed amine/ phosphine adducts. Figure 13 presents the different coordination modes that have been observed so far. 

The most striking structural difference between analogously substituted, base-stabilized monomeric alanes is reflected by the degree of pyramidaliza-tion of the group 15 element. The sum of the bond angles of the pentele center (sum of the Si-E-Si and Si-E-Al bond angles) of the Me-substituted... 

Stibinoalanes, 262-264, 266-268, 269 for AlSb film deposition, 301-303 see also Alane stibine adducts Stibinogallanes, 261-262, 269-272, 294-295 in film deposition, 303 Stibinoindanes, 261-262, 264, 272, 273 in film deposition, 303-304 Structure... 

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