Configurational studies

DE 3 540 093 (Farmitalia Carlo Erba appl. 12.11.1985 GB-prior. 22.11.1984). configurational studies on 2-la-(2-ethoxyphenoxy)benzyl]morpholine ... 

The main factor in determining the handedness of the cholesterics induced by bridged 1,1 -binaphtliyls is the helicity (P or M) of the solute, and this observation is the basis of many configurational studies of chiral binaphthyls. All the homochiral (aP)-binaphthyls 15-19 have an M helicity of the core, and all induce, in biphenyl nematics, M cholesterics.65,75 By systematic structural variations of the covalent bridge, it is possible to obtain I J -binaphthalenes with dihedral angles ranging from 60° to 96° (see series 20-24) the handedness of the cholesteric phase always matches the helicity... 

The recently introduced lanthanide-induced shift (LIS) technique has also found useful application in configurational studies of sulfur compounds. For example, the absolute configurations of a new type of bridged steroidal sulfoxide 203, which is epimeric at sulfur, were... 

One of the desirable features of compact wavefunctions is the ability to use them to examine additional features of the electron distribution without the necessity of repeating extensive computations to recreate complicated wavefunctions. We illustrate this point, and also exhibit the similarity of our wavefunctions with those of the 66-configuration study of Thakkar and Smith [15] by looking at the pair distribution functions. It is most instructive to present these as Z-scaled quantities Figure 3 contains the electron-nuclear distributions D r ) and p(ri) for clarity we only plot data for H, He, Li, and Ne. Even after Z scaling, a small but systematic narrowing of the distributions with increasing Z is still in process at Z-10. 

Mole balance expressions were developed for a general series reaction by Agarwalla and Lund [16], and the same procedures were used here to develop the species balance equations shown in Table I. Boundary conditions and parameter definitions are presented in Tables II and III. Note that the boundary conditions are given only for co-current flow of reactants and inert, which is the only configuration studied. Previous work [16], has shown that counter-current operation is less effective than co-current operation. 

With respect to stereoselective synthesis, the application of CD spectroscopy is further reduced to a rather narrow range of functional (chromophoric) groups which are most frequently present in the product of synthesis in the vicinity of the newly formed stereogenic center. All this should not by any means discourage the use of CD spectroscopy for configurational studies. Rather, it is meant to show the intrinsic limitations of the method. 

Currently there is great interest in alternate fuels manufacture, and plant configuration studies are published by the dozen. Such configurations usually include a "Claus process" box all too often the material fed into the box could not be handled by any known Claus-type process. This paper is meant to point out some of the problems needing recognition, and some of the solutions. One solution is a new process suited to some coal gasifiers. 

ESC and ETC diesel oxidation catalyst simulation results in Fig. 53 show that the N02/NOx ratio behind the DOC varies from 30% to 60% over the ESC and from 10% to 80% over the ETC for the configuration studied, with a mean value of approximately 40%. Using these simulated N02/NOx ratios behind the DOC as input for the SCR test cycle simulations, lower conversion efficiencies are obtained compared to the 50% N02 case. However, Fig. 54 and the values in Table VII indicate that there is still a significant increase in the total NOx conversion compared to the simulation without N02 in the inlet feed. This also confirms that the chosen DOC geometry and volume is quite well adapted to the specific application. 

Gaset, A., Lafaille, L., Verdier, A., and Lattes, A., Infrared spectra of a-aminoketones configurational study and evidence of an enol form, Bull. Soc. Chim. Fr., 10, 4108, 1968. 

The electron density and its Laplacian have been correlated exponentially with the HB distance. These results are in agreement with other reports that show the generality of this rule [120-122]. The dimers of a series of chiral and nonchiral a-aminoalcohols were studied by means of DFT methods (B3LYP/6-311++G ) (Scheme 3.14). Due to the flexibility of the molecules, twelve possible complexes can be proposed in the case of the chiral molecules. Half of them are mirror image of the other half, and thus, only six where considered. The six unique configurations studied for each dimer (Scheme 3.15) correspond to three homochiral dimers (RR or SS) and three heterochiral ones (RS or SR), and can be grouped in three chairs, Cl-3, and three boats, Bl-3, respectively. 

The configurational studies so far outlined neatly correlate the more active antipodal isomers of the methadone and isomethadone type, respectively. 

Concentration and temperature profiles like those shown in Figure 3.6 are idealizations. In recent years a number of profile measurements have been made in laminar diffusion flames (for instance, [80], [162]-[168]). Configurations studied include porous spheres [80] and cylinders [163],... 

---