Directing effects predicting products

Treatment of l,2-difluoro-3,5-dinitrobenzene with methoxide leads to a single isomer of fluorodinitroanisole. Obtain the energies of the possible Meisenheimer complexes and predict the structure of the product. Is this outcome consistent with the previously-established directing effect of the nitro group ... 

Energy levels of heavy and super-heavy (Z>100) elements are calculated by the relativistic coupled cluster method. The method starts from the four-component solutions of the Dirac-Fock or Dirac-Fock-Breit equations, and correlates them by the coupled-cluster approach. Simultaneous inclusion of relativistic terms in the Hamiltonian (to order o , where a is the fine-structure constant) and correlation effects (all products smd powers of single and double virtual excitations) is achieved. The Fock-space coupled-cluster method yields directly transition energies (ionization potentials, excitation energies, electron affinities). Results are in good agreement (usually better than 0.1 eV) with known experimental values. Properties of superheavy atoms which are not known experimentally can be predicted. Examples include the nature of the ground states of elements 104 md 111. Molecular applications are also presented. 

When the directing effects of two or more substituents conflict, it is more difficult to predict where an electrophile will react. In many cases, mixtures result. For example, o-xylene is activated at all the positions, so it gives mixtures of substitution products. 

From a control standpoint it is important to know the actual form of the kinetic rate expression. The reason is that it dictates which reactant and product components play a dominant role on the behavior of the reactor. For example, components with a nonzero exponent play a direct and predictable role especially at low concentrations. But even components that don t enter the rate expression le.g., inerts) play,an indirect role by their influence on the concentrations of the reactants. This secondary effect is much less predictable for a multicomponent system. In general, it is seldom easy to determine the composition effects of a single component from a superficial look at the reaction... 

What happens in electrophilic aromatic substitution when a disubstituted benzene ring is used as starting material To predict the products, look at the directing effects of both substituents and then determine the net result, using the following three guidelines. 

On the other hand, when the directive effect of one group opposes that of the ler, it may be difficult to predict the major product in such cases complicated xtures of several products are often obtained. 

When a disubstituted benzene undergoes an electrophilic aromatic substitution reaction, the directing effect of both substituents has to be considered. If both substituents direct the incoming substituent to the same position, the product of the reaction is easily predicted. 

Promoting the sustainable development implies the availability of reliable measures. These measures should regard the complete manufacturing-supply chain over the predictable product life cycle. The metrics should be simple and understandable by the large public, useful for decision-making agents, consistent and reproducible. The sustainability measures proposed recently by Schwartz, Beloff Beaver (2002) have these properties. They refer to the same unit of outputs, for example the to the value-added dollar Fy4, defined as Revenues minus Costs of raw materials and utilities. The metrics that will be presented are consistent in the sense that 1) the lower the metric the more effective the process, and 2) all indicate the same direction. 

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