Criteria for synthesis

It is often true, however, that synthesis of a particular target is of paramount importance to an individual or organization. The criteria for that importance is always obvious to the researcher(s). To one beginning a study of organic reactions and synthesis, however, it may be of value to examine several commonly quoted criteria for synthesis. These criteria, along with Corey s and Deslongchamps evaluations, provide a reasonable answer to question (1). The disconnection approach in its several forms will be used to address Question 2. 

To increase the potency of the above similarity criteria for synthesis design, they have been integrated into a system that allows a user to specify strategic bonds. Bonds chosen by the chemist as strategic for a synthesis are broken and the fragments (synthons) are converted into neutral molecules. These building blocks for a synthesis are then analysed by the similarity measures. 

Current research in LHASA is focused on developing new methods assisting users in choosing the most appropriate strategy for their target structures. Furthermore, the development of criteria for the evaluation of synthesis routes and/or algorithms for selecting optimal synthesis routes within the tree are discussed [34]. 

Hydrothermal Synthesis Systems. Of the unit operations depicted in Figure 1, the pressurized sections from reactor inlet to pressure letdown ate key to hydrothermal process design. In consideration of scale-up of a hydrothermal process for high performance materials, several criteria must be considered. First, the mode of operation, which can be either continuous, semicontinuous, or batch, must be determined. Factors to consider ate the operating conditions, the manufacturing demand, the composition of the product mix (single or multiple products), the amount of waste that can be tolerated, and the materials of constmction requirements. Criteria for the selection of hydrothermal reactor design maybe summarized as... 

Since a few protective groups cannot satisfy all these criteria for elaborate substrates, a large number of mutually complementary protective groups are needed and, indeed, are becoming available. In early syntheses the chemist chose a standard derivative known to be stable to the subsequent reactions. In a synthesis of callistephin chloride the phenolic —OH group in 1 was selectively protected as an acetate. In the presence of silver ion the aliphatic hydroxyl group in 2 displaced... 

C2. Calculation of Operating conditions and Transport Criteria for the UCKRON Test Problem as a Methanol Synthesis Experiment in the Rotoberty ... 

For commercial ionic liquid synthesis, quality is a key factor. FFowever, since availability and price are other important criteria for the acceptance of this new solvent concept, the scaling-up of ionic liquid production is a major research interest too. 

The challenge in the synthesis of chemical libraries is the vast number of different, potentially drug-like small molecules which is estimated to be as high as 1060. As all of these molecules can never be synthesized and tested, it is essential to define criteria for the composition of libraries spanning the biologically relevant areas of the chemical space most efficiently. An important criterion of a compound library is its chemical diversity, a term describing the similarity or dissimilarity of all library components. Thus, chemical diversity expresses how well a library represents all theoretical possibilities within the chemical property space. A library with low... 

The Editorial Board lists the following criteria of content for submitted manuscripts Style should conform with that of previous volumes of Inorganic Syntheses. The Introduction should include a concise and critical summary of the available procedures for synthesis of the product in question. It should also include an estimate of the time required for the synthesis, an indication of the importance and utility of the product, and... 

The purpose of this review is to provide the reader with a scenario of what can be accomplished with nickel complexes. It is useful to do this via a series of broad schemes, hypothetical in some cases, which show the main reaction patterns, without considering mechanistic details. Examples will illustrate the various processes, but extension to other substrates or to different conditions often requires use of alternative ligands or solvents, or a change from a neutral complex to a cationic or anionic species, as indicated above. For references to syntheses with nickel see Baker et al. (10). For criteria for the synthesis of coordination compounds and stability of organotransition metal complexes in general, see references (11. 12). Organometallic literature has been collected periodically by Bruce (13). 

The convergent approach to dendrimer synthesis has evolved considerably over the past dozen years. With the benefit of hindsight, it is clear that the key criteria for a successful convergent synthesis include ... 

The search for regularities and criteria for the synthesis of new representatives of particular structure types has been carried out by many authors. Several factors have been recognized to be important in controlling the structural stability, and some of these were used as coordinates for the preparation of classification and prediction maps in which various compounds can be plotted and separated into different structure domains. 

Many studies have been directed toward the empirical development of synthetically effective reagents for asymmetric reductions. Criteria for an efficient asymmetric synthesis have been summarized by Eliel (12) as follows ... 

Fig. 10.4 Diagram outlining criteria for successful use of high-throughput synthesis/screening approaches to materials discovery and exploration.

The criteria for the thermally decomposable coblock include the synthesis of well-defined functional oligomers, compared with the synthesis of polyimide. This block must also decompose quantitatively into non-reactive species that can easily diffuse through a glassy polyimide matrix. The temperature at which decomposi-... 

The discussion so far has described how libraries of potentially active chemical compounds can be produced using solid-phase synthesis. The next question—and a crucial question it is—is which of those compounds meet the basic criteria for which the experiment was intended One might ask, for example, which compounds of all those in the library are actually potent in the treatment of some disease. The process by which the structure of any active compound present in a mixture of compounds is identified is called deconvolution. Deconvolution is often one of the most time-consuming steps in any combinatorial procedure. 

Table 2.1. Criteria for chain and stepwise reactions in polymer synthesis...

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