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The N-alkylation of primary nitrophenylsulfonamides followed by removal of the nitrophenylsulfonamide moiety under nucleophilic conditions to provide secondary amines has become an established literature procedure. Application of this methodology with less reactive alkylating agents can give rise to side products resulting from a nitrogen to carbon transfer of the nitrophenyl ring. This side product predominates when tetrabutylammonium hydroxide is used in place of metal carbonate bases in the N-alkylation step.

The bifunctionality of amino acids can be exploited by utilizing them as quenchers in rapid solution phase parallel synthesis. The amino group was used to covalently trap the excess electrophiles, whereas the carboxylic acid moiety was used to solubilize the derivatized amino acid in water. As a prototype we used potassium sarcosinate as a quencher for excess electrophiles in the acylation or sulfonation of N-methyl-benzylamine. Various electrophilic reagents such as acid chlorides, isocyanates and sulfonyl chlorides were quenched successfully to give pure products in excellent yields.

The bifunctionality of amino acids can be exploited by utilizing them as quenchers in rapid solution phase parallel synthesis. The amino group was used to covalently trap the excess electrophiles, whereas the carboxylic acid moiety was used to solubilize the derivatized amino acid in water. As a prototype we used potassium sarcosinate as a quencher for excess electrophiles in the acylation or sulfonation of N-methyl-benzylamine. Various electrophilic reagents such as acid chlorides, isocyanates and sulfonyl chlorides were quenched successfully to give pure products in excellent yields.

Merrifield resin is converted to a solid-supported free radical initiator by reacting with the TEMPO-Na. Heating TEMPO-methyl resin with a variety of functionalized styrene and acrylate monomers gives larger resin beads via living free radical polymerization. We have coined the term Rasta resin to describe resin beads prepared in this fashion. The process can be described as a solvent-free suspension polymerization. It is particularly well suited for preparation of resin beads from monomers which contain electrophilic groups that would be destroyed upon suspension polymerization in water. Rasta resins have a novel macromolecular architecture wherein long straight chain polymers bearing reactive functional groups emanate from the phenyl groups of a cross-linked polystyrene core. With judicious choice of co-monomers and polymerization strategy, the solvent affinity, loading capacity, and distance of functionality from the cross-linked core may be controlled giving beads with properties that are tailored to specific uses as synthesis supports and scavenging resins.