2-(4-tolylsulfonyl)ethoxymethyl (TEM) as a new 2'-OH protecting group is reported for solid-supported RNAsynthesis using phosphoramidite chemistry. The usefulness of the 2'-O-TEM group is exemplified by the synthesis of 12 different oligo-RNAs of various sizes (14-38 nucleotides long). The stepwise coupling yield varied from 97-99% with an optimized coupling time of 120 s. The synthesis of all four pure phosphoramidite