Hydroxymethyl Polystyrene

These resins are alternatives to the corresponding chloromethylated resins (Merrifield resins) and ideal for the attachment of acids by esterification. Diacids can be attached with less crosslinking compared to Merrifield resins. Release of the carboxylic acid from the resin can be effected by treatment with HF, trifluoromethane sulfonic acid or hydrogenolysis. Liberation of alcohols is established by reduction with DIBAL or LiBH4. Methyl esters can be produced by transesterification with MeONa or Ti (OEt) 4/methyl propionate. Carboxamides are accessible by Lewis acid catalyzed aminolysis.