Used in oligonucleotide synthesis, particularly in the preparation of DNA probes and primers for molecular biology applications. It enables the incorporation of ethynyl-modified nucleosides into synthetic DNA strands, which can be further functionalized via click chemistry for labeling, detection, or immobilization on solid supports. Commonly applied in diagnostic assays, gene sequencing, and antisense oligonucleotide development due to its efficient coupling and compatibility with automated synthesizers.