Crystal structure studies

Models for copper-protein interaction based on solution and crystal structure studies. R. Osterberg, Coord. Chem. Rev., 1974,12, 309-347 (130). 

The initial work in this field appeared as a communication in 1969 8), and this work was later expanded to a full paper (9). Badley et al. described the synthesis of m-Pt(PEt3)(CNCjH5)Cl2 from Pt2(PEt3)2Cl4 and the isocyanide the bromide complex could be obtained from this complex by addition of bromide ion. These complexes were then observed to react with various substances [Eq. (16)]. A crystal structure study on the complex... 

In addition, several addition reactions have been reported for the iron complex [Fe(CNCH3)j] with hydrazine and with methylamine (99) the products (XVI) and (XVII), respectively, are described. A crystal structure study on the latter compound was carried out. 

A crystal structure study on /ac-Mn(CO)3(CNCH3)2Br has been done 133). 

The volume expansion accompanying the spin-state transition has been demonstrated, at least in quantitative terms, on the basis of multi-temperature crystal structure studies [6]. An alternative method starts from the determination of the lattice constants as a function of temperature and therefrom, the volume of the unit cell may be calculated at each temperature. It has been shown [70] that the variation of the unit cell volume V(T) may be reproduced by ... 

Thiosemicarbazone (RNH-CS-NH-N=CR/R//, tsc) complexes of cobalt(III) have been extensively studied since the early 1980s and continue to attract attention, gaining particularly from an interest in their biological activity and potential cytotoxicity. A truly extensive range of tsc compounds has now been reported, although structural definition of their complexes widely relied on basic analytical and spectroscopic techniques up to the late 1980s, when X-ray crystal structural studies of tsc compounds became more common. A review of thiosemicarbazone and S-alkyldithiocarbazate complexes has appeared.1053... 

The enantioselective photoreaction of 50 to 52 in the complex (57) can be interpreted as follows disrotatory [2 + 2]-photoreaction of 50 in 51 occurs only in the A direction according to a steric hindrance of the o-chlorophenyl group of 2a (Scheme 4)29 30). This interpretation was determined as reasonable by X-ray crystal structural study of 51b (Fig. 12)32). 

Since one unit of 59 contains one molecule of 58 and two molecules of 2a, at least two of these units should take part in the photodimerization of 58. In other words, four molecules of 2a are concerned in each photodimerization of 58. It is not clear at present whether this has something to do with the relatively high enantioselectivity and efficiency of the photodimerization or not. In future, an X-ray crystal structural study of 59 is required to clarify this question. As in the case of 37, 58 exists as an equilibrium mixture of two flipping optical conformers. We may also learn from an X-ray analysis which optical conformer is included in 59. 

The configurations at phosphorus in compounds 73-76 were assigned on the basis of II-NMR data assuming that in phosphorus-containing heterocycles, the protons in a 1,3-m-relation to a P=0 group are deshielded. Thus, since H4 and H5 resonate at lower field in compounds 73a-76a than in compounds 73b-76b, the P=0 group must be cis to H4 and H5 in the a series [32]. These assignments were fully supported by the crystal structure studies of 75a, which showed that this... 

Crystal Chemical Studies of the 5/-Series of Elements. VIII. Crystal Structure Studies of Uranium Silicides and of CeSia, NpSi3 and PuSia. Acta crystallogr. (London) 2, 94 (1949). 

The question as to the best formulation of structures and species in some binary fluoride systems was the subject of extensive experimental investigations, involving infrared and Raman spectroscopy in the molten state and in solutions as well as NMR spectroscopy and conductometric and cryoscopic measurements. Some crystal structure studies have also been published. The systems of SeF4 with BF3, SbF5, AsF5, NbF5, and TaFs have been studied recently. 

Recently, by crystal structure studies the number of different polymorphs of Copper Phthalocyanine Blue has been extended to nine, various of which are differing mainly in herringbone-type interaction [17]. 

S. Klotz, J. M. Besson, G. Hamel, R. J. Nelmes, J. S. Loveday, W. G. Marshall, and R. M. Wilson, Crystal structure studies to 10 GPa with the Paiis-Edinburgji cell high pressure aspects in High-Pressure Science and Technology, S. C. Schmidt, J. W. Shaner, G. A. Samara, and M. Ross, eds. AIP Press, New York, 1993, pp. 1577-1580. 

Crystal Structure Studies of Amino Acids and Peptides... 

Similar irradiation of the 1 1 complex of tropolone ether 10b and host compound 8 led to photoproducts 11b (100% ee) and 12b (72% ee) in 12 and 14% yields, respectively. The authors interpreted these reactions as follows disrotatory electrocyclic closure of tropolone derivative 10 to afford photoproduct 11 in the inclusion crystals occurs in only one direction owing to the steric hindrance of host 8. This interpretation appeared to be reasonable based on an examination of the X-ray crystal structure study of the inclusion complex [18]. Formation of keto-ester 12 takes place by a more complex mechanism... 

As far as I know, crystal structure studies have not been published on this kind of compound. But I think they would be revealing and by analogy perhaps tell us something about the melt situation. If one can determine—and I am sure it is possible by x-ray analysis of these compounds—what the nitrate coordination is around the metal ion, one might be able to infer something about the melt situation. 

ILs [18,19,50]. This is especially so when done in combination with crystal structure studies, as explained in the following ... 

X-ray crystal structure studies have been reported for three oxetanes (4), 3,3-bis(trimethylaminomethyl)oxetane methanesulfonate and the 3,5-dinitrobenzoate ester of threo-a,3,3,-4,4-pentamethyloxetanemethanol (5). These compounds were all non-planar, with dihedral angles of 16, 29.4 and 8°, respectively (73CC34,71DIS(B)(32)1445,78CSC309). 

Oth Mullen Gilles Schroder Helv. Chim. Acta 1974, 57,1415 Nakanishi Yamamoto Tetrahedron Lett. 15174, 1803 Gunther Ulmen Tetrahedron 1974, 30, 3781. For deuterium nmr spectra see Poupko Zimmermann Luz J. Am. Chem. Soc. 1904, 106, 5391. For a crystal structure study, see Luger Buschmann McMullan Ruble Matias Jeffrey J. Am. Chem. Soc. 19 6,108. 7825. 

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