The Application of Immobilized Reagents and Scavengers to Library Synthesis

2 The Application of Immobilized Reagents and Scavengers to Library Synthesis 

Many of the routes reported for the construction of diverse chemical libraries are often constrained by the commercial availabihty of the monomer sets used as the primary building blocks. While there are a large number of simple starting materials currently available, chemists would prefer to have ready access to more sophisticated and highly functionahzed monomer units which would lead rapidly to drug-like molecules. 

Polymer-supported permthenate has also been used in two convergent pathways for the synthesis of isoxazoUdines with each route employing different starting materials in order to create the maximum structural diversity [73]. In the first route secondary hydroxylamines, readily prepared from amines by in situ treatment with dimethyldioxirane, were oxidized directly to nitrones using polymer-supported permthenate (PSP). Alternatively, primary alcohols were used as the 

Under carefully controlled conditions the selective mono bromination of an electronically diverse range of acetophenone derivatives can be realized using the polymer-supported pyridinium perbromide reagent. The resultant a-bromoketone 

Multi-component condensation reactions offer tremendous scope for increasing diversity in combinatorial chemistry programs since, in a single reaction, structurally advanced compounds can be realized from very simple starting materials. In 

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