New Synthetic Strategies

In several important cases, new synthetic strategies have been developed into new production schemes. An outstanding example of this is the production of an entire family of terpene derivatives from a-pinene (29), the major component of most turpentines, via linalool (3) (12). Many of these materials had been produced from P-pinene, a lesser component of turpentine, via pyrolysis to myrcene and further chemical processing. The newer method offers greater manufacturing dexibiUty and better economics, and is environmentally friendly in that catalytic air oxidation is used to introduce functionality. 

In the recent decades, an enzyme-catalyzed polymerization ( enzymatic polymerization ) has been of increasing importance as a new trend in macro-molecular science. Enzyme catalysis has provided new synthetic strategy for useful polymers, most of which are difficult to produce by conventional chemical... 

Hanessian, S., Bedeschi, A., Battistini, C., MongeUi, N. (1985) A New Synthetic Strategy for the Penems. Total Synthesis of (5R,6S,8R)-6-(a-Hydroxyethyl)-2-(hydroxymethyl)penem-3-carboxylic Acid. Journal of the American Chemical Society, 107, 1438-1439. 

This reaction looks simple, but an enzyme-free prebiotic synthesis, in particular involving pyrimidine bases, is still very difficult. It is possible that completely new synthetic strategies will need to be devised. 

R. Jager, F. Vogtle, A New Synthetic Strategy towards Molecules with Mechanical Bonds Nonionic Template Synthesis of Amide-Linked Catenanes and Rotaxanes , Angew. Chem Int. Ed. Engl. 1997,36,930-944. 

Almost all modifications in PF homopolymers consist of variation of substituents at position 9 of the fluorene nucleus. Recently, Beaupre and Leclerc [303] reported a new synthetic strategy to polymers 201 and 202 with the aim to modulate the 7P of the PFs (for better injection of holes from the anode in LED) by introducing donor 3,6-dimethoxy substituents into the fluorene moiety (Scheme 2.27). The d>PL of polymer 201 is relatively low (48%), but it... 

D Acquarica, L, New synthetic strategies for the preparation of novel chiral stationary phases for high-performance liquid chromatography containing natural pool selectors, J. Pharm. Biomed. Anal, 23, 3, 2000. 

Examples taken either from his own laboratory or from the recent chemical literature allow Curran to show how retrosynthetic analysis can generate ideas for new methods and reagents, as well as for new synthetic strategies in which homolytic cleavage of bonds are taken into account. 

In order to search new synthetic strategies to build up novel families of organomet-allic-containing dendritic macromolecules, we explored pathways that would allow... 

This short review has described the synthesis of Lewis acid-base adducts and heterocyclic group 13/Sb compounds. In particular the synthesis of the hete-ro cycles required the development of new synthetic strategies. The distibine... 

In the field of organic chemistry, new synthetic strategies and methodologies are developed at an astonishing rate to access a diverse range of molecules. 

Jager, R., Vogtle, F. (1997) A new synthetic strategy towards molecules with mechanical bonds. An-gew. Chem. Int. Ed. Engl. 36, 930-944. 

Various other surface chemistries have been used to attach chemical species to electrode surfaces. For example, Watkins et al. activated the carboxylic acid functionalities on carbon electrodes with thionyl chloride and then reacted this surface with amines [17]. Sagiv and his coworkers have recently invented a clever approach for monolayer-by-monolayer deposition of multilayer films based on organosilane chemistry [18]. Finally, Mallouk et al. have also developed a monolayer-by-monolayer approach for synthesizing well-ordered multilayer films [19]. Because of these interesting new synthetic strategies, covalent attachment of functional groups remains an attractive approach for modifying electrode surfaces. 

The 4,8-dihalotetracyclooctasilane starting materials were synthesized by treating the octasilacubane with PCI5, Br2 or I2, respectively (equation 26). Thus, not really a new route to octasilacubanes has been discovered, but a new mechanism, which might be able to provide an entry into new synthetic strategies. 

Also, while there are some more recent examples of synthetic approaches to spirocyclic systems incorporating azepine or benzazepine structural moieties, the scope to devise new and versatile approaches is still significant. Spirocyclic systems continue to hold considerable promise as scaffolds for the design of new pharmaceutical agents and new synthetic strategies would be of benefit in this area. 

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