Provided are processes for preparing a 3'-deoxypentopyranosyl oligomers with linkers for linking biomolecules. The processes can the steps of: bonding a 4'-protected-3'-deoxypentopyranosyl nucleoside to a solid support by coupling the 2'-OH group with a CPG support or other similar support with an amide linkage; deprotecting the 4'-protected-3'-deoxypentopyranosyl nucleoside at the 4' position; deprotecting the 4'-protected-3'-deoxypentopyranosyl nucleoside at the 4' position; and conjugating a linker to the free 4' position. The resulting product can be conjugated via the linker to a biomolecule. The method can include, prior to addition of the linker, reacting the 4'-OH group of the 4'-protected-3'-deoxypentopyranosyl nucleoside that is linked to the solid support with a 4'-protected-3'-deoxypentopyranosyl nucleoside phosphoramidite in the presence of a coupling reagent, and oxidizing the reaction product. This step can be repeated one or more times to produce an oligomer of desired length.