Methods of forming an internucleotide bond are disclosed. Such methods find use in synthesis of polynucleotides. The method involves contacting a functionalized support with a precursor having an exocyclic amine triaryl methyl protecting group under conditions and for a time sufficient to result in internucleotide bond formation. The functionalized support includes a solid support, a triaryl methyl linker group, and a nucleoside moiety having a reactive site hydroxyl, the nucleoside moiety attached to the solid support via the triaryl methyl linker group. In particular embodiments, the precursor has the structure:wherein:O and H represent oxygen and hydrogen, respectivelyR1 is hydrido, hydroxyl, protected hydroxyl, lower alkyl, modified lower alkyl, or alkoxy,one of R2 or R3 is a hydroxyl protecting group; and the other of R2 or R3 is a reactive group capable of reacting with the reactive site hydroxyl,Base is a heterocyclic base having an exocyclic amine group, andTram is the exocyclic amine triaryl methyl protecting group.