Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Organic synthesis evaluation

Such techniques mean that the chemical literature may be used more effectively, and that its use can be partially automated. Might this lead to a way of automating organic synthesis To make most molecules there are many strategies which may be successful. If each reaction of each strategy can be evaluated for similarity to a reaction recorded in the literature, it should be possible to develop a route to most molecules by mechanically searching the chemical literature, so that suitable precedent is found for every transformation. [Pg.53]

Fuchs, P.L. (2001) Increase in Intricacy - a Tool for Evaluating Organic Synthesis. Tetrahedron, 57, 6855-6875. [Pg.189]

Friedel-Crafts alkylations are among the most important reactions in organic synthesis. Solid acid catalysts have advantages in ease of product recovery, reduced waste streams, and reduction in corrosion and toxicity. In the past, people have used (pillared) clays (18), heteropolyacids (19) and zeohtes (20) for Friedel-Craft alkylations, with mixed success. Problems included poor catalyst stabihty and low activity. Benzylation of benzene using benzyl chloride is interesting for the preparation of substitutes of polychlorobenzene in the apphcation of dielectrics. The performance of Si-TUD-1 with different heteroatoms (Fe, Ga, Sn and Ti) was evaluated, and different levels of Fe inside Si-TUD-1 (denoted Fei, Fe2, Fes and Feio) were evaluated (21). The synthesis procedure of these materials was described in detail elsewhere (22). [Pg.372]

The purpose of preparative-scale liquid chromatography is the isolation of materials conforming to a specified purity in cUBOunts that depend on the intended use of the product [8,570-572]. Possible uses Include the isolation of materials for structural elucidation, for biological or sensory evaluation, for organic synthesis or commercial applications. The scale of the... [Pg.764]

The methods of organic synthesis have continued to advance rapidly and we have made an effort to reflect those advances in this Fifth Edition. Among the broad areas that have seen major developments are enantioselective reactions and transition metal catalysis. Computational chemistry is having an expanding impact on synthetic chemistry by evaluating the energy profiles of mechanisms and providing structural representation of unobservable intermediates and transition states. [Pg.1328]

Due to the availability of chemical libraries, plant and microbial extracts and rapid screening methods lead compounds are rapidly identified. When the structures of PTKs are known optimization by organic synthesis and computer modeling follows. Compounds that successfully pass all the screening tests are ready to be evaluated for clinical trials. [Pg.10]

Fundamental criteria to evaluate the results of any organic synthesis are the yield , being the fraction of the entire supplied reactant, which has formed the product, and the selectivity , being the fraction of the converted reactant, which has been used to generate the product. [Pg.31]

It is hoped that the examples cited have provided the reader with a sense of the wide range of exceptionally useful transformations that can be carried out elec-trochemically. It is hoped that some day this protocol will be routinely considered, evaluated for its unique merits, and widely adopted as a tool that is to be used to solve problems in organic synthesis. [Pg.336]

Cathodic cyclization reactions have supphed and continue to provide a fertile territory for the development and exploration of new reactions and the determination of reaction mechanism. Two areas that appear to merit additional exploration include the application of existing methodology to the synthesis of natural products, and, more significantly, a systematic assessment of the factors associated with the control of both relative and absolute stereochemistry. Until there is a solid foundation to which the non-electrochemist can confidently turn in evaluating the prospects for stereochemical control, it seems somewhat unlikely that electrochemically-based methods will see widespread use in organic synthesis. Fortunately, this comment can be viewed as a challenge and as a problem simply awaiting creative solution. [Pg.46]

In initial work, a total of 17 different ILs were evaluated by the solvation parameter model [8]. Ten of these ILs were comprised of imidazolium or pyrolidinium cations paired with different anions. Many of these compounds represent the traditional class of IL solvents that have been used extensively in organic synthesis reactions or in other analytical uses. The remaining seven ILs consisted of substituted ammonium cations that have proven to be successful analyte matrices in matrix-assisted laser desorption ionization (MALDI) mass spectrometry [11]. [Pg.147]

Optically pure l,l -binaphthol and its derivatives have been evaluated as versatile chiral auxiliaries and ligands in asymmetric transformations. Research in this area has provided many efficient and useful methods for the preparation of key chiral building blocks, some of which have been used for the construction of complex natural products. The wide ranging and important applications of such compounds in organic synthesis have stimulated great interest in developing efficient methods... [Pg.267]

In addition to the larger families of preparatively useful aldolases, some less common aldolases have been evaluated lately for preparative use. A range of mechanistically distinct enzymes, which are actually categorized as transferases but which also catalyze aldol-related additions through the aid of cofactors such as pyridoxal 5-phosphate (PLP), thiamine pyrophosphate (TPP), tetrahydro-folate (THF), or coenzyme A (CoA), are becoming more frequently applied in organic synthesis. Because of their emerging importance and/or commercial availability, a selection of these enzymes and examples of their synthetic utility will be included in further separate chapters. [Pg.102]


See other pages where Organic synthesis evaluation is mentioned: [Pg.263]    [Pg.263]    [Pg.550]    [Pg.423]    [Pg.4]    [Pg.31]    [Pg.32]    [Pg.302]    [Pg.460]    [Pg.300]    [Pg.811]    [Pg.77]    [Pg.87]    [Pg.109]    [Pg.405]    [Pg.178]    [Pg.383]    [Pg.425]    [Pg.324]    [Pg.111]    [Pg.14]    [Pg.195]    [Pg.199]    [Pg.411]    [Pg.412]    [Pg.428]    [Pg.307]    [Pg.367]    [Pg.159]    [Pg.128]    [Pg.17]    [Pg.294]    [Pg.97]    [Pg.75]    [Pg.174]    [Pg.363]    [Pg.430]    [Pg.529]    [Pg.40]    [Pg.177]   
See also in sourсe #XX -- [ Pg.232 ]




SEARCH



© 2024 chempedia.info