Used as a reagent in the synthesis of oligonucleotides, particularly in solid-phase DNA synthesis. It acts as a phosphitylating agent, enabling the formation of phosphite triester linkages between nucleotide units. Its structure provides enhanced stability and reactivity, making it suitable for automated DNA synthesizers. Commonly employed in the preparation of antisense oligonucleotides, primers for PCR, and other nucleic acid analogs used in molecular biology and therapeutic applications.