Solid-support-based methodology

Synthetic oligonucleotides are very important tools in the study and manipulation of DNA, including such techniques as site-directed mutagenesis and DNA amplification by the polymerase chain reaction (PCR). The techniques for chemical synthesis of oligonucleotides have been highly developed. Very efficient and automated methodologies based on synthesis on a solid support are used widely in fields that depend on the availability of defined DNA sequences.152... 

The above described methodology was found to be very useful in a solid-supported synthesis of pyrazoles and pyrimidines via propenones developed by Westman and co-workers35 (Scheme 5.19). Merrifield resin was reacted with methylamine in water at 150°C for 10 min to form the solid-supported benzylmethylamine (3) in high yield (86% yield, 1.08 mmol/g based on elemental analysis). After washing, the resin was treated with 5 equiv. DMFDEA and 5 equiv of 4-phenoxyacetophenone at 180°C for 10 min in DMF to form the solid supported benzyl methyl aminopropenones (4). 

Munk and co-woricers have been concerned with the above-stated problem for some time (38, 39). In this volume (40), their attention is focused on miscible blends of polycaprolactone and polyepichlorohydrin. These authors demonstrate that to a considerable degree the probe variation problem can be mitigated by scrupulous attention to experimental details in the IGC methodology. This concern for details is required at any rate, if the high data reproducibility needed for meaningful studies of interaction in miscible polymer blends is to be attained. These details center on modified methods for coating polymers onto solid supports, on improved methods for measuring carrier gas flow rates, and on enhanced, computer-based data analyses of elution traces. Also, corrections are made for contributions to retention times from uncoated support material. More than twenty volatile probes are used by Munk, and the probe-to-piobe variations in %23, while not entirely absent, are much less apparent than they would be under standard experimental protocols. 

This chapter begins with a general description of the several strategies to het-erogenize transition-metal complexes onto solid supports, with a special emphasis on those methodologies that have been used for complex grafting onto carbon materials. It will include sections that will focus on the various transition-metal complexes that have been immobilized onto several carbon materials activated carbons, black carbons, carbons xerogels, and carbon nanotubes the specific catalytic reactions with these carbon-based systems are also discussed in some detail. 

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