2. Supports

2.1 Linear skeletons

Linear backbone polymers are soluble in certain organic solvents, enabling reactions to be carried out in homogeneous media, without diffusion problems, with equal accessibility of all supported reaction sites and classical kinetics. What's more, immobilized substrates can be characterized using standard analytical techniques. Finally, precipitation of the polymer by addition of a non-solvent makes filtration possible. However, precipitation is not always total and selective, sometimes leading to separation and purification problems.

The linear polymers most commonly used in organic synthesis are polyethylene glycol (PEG) 1, polyethylene glycol monomethyl ether (MPEG) 2 and linear polystyrene (