Simple and Efficient Solution-Phase Synthesis of Oligonucleotides Using Extractive Work-Up

A solution-phase synthesis protocol amenable to scale-up was developed for the preparation of oligonucleotides employing phosphoramidite chemistry and DMTr/iBu/Bz-protected monomers. Isolation of intermediates was accomplished by means of extractions as the only purification tool. The potential of the method is demonstrated with the synthesis of a hexameric DNA fragment in high yield and purity.