Exploring Stibanyl Ligand for Accessing Arsinidene\nand Arsaketene Adducts, and Phosphaketene

The\nsalt metathesis reaction involving a diamine-based antimony\nchloride precursor with sodium arsaethynolate in the presence of PMe<sub>3</sub> leads to the formation of stibanyl-functionalized PMe<sub>3</sub>-arsinidene (<b>2</b>). Detailed analyses through single-crystal\nX-ray diffraction and density functional theory of <b>2</b> confirm\nthe presence of covalent Sb–As bonds and reveal its polarized\nnature with a multiple-bond character. In contrast to the formation\nof complex <b>2</b>, substituting PMe<sub>3</sub> with xylyl\nisocyanide or 1,3-diisopropyl-4,5-dimethyl-imidazolin-2-ylidene (<b>I</b><i>i</i><b>Pr</b>) produces an isocyanide-arsinidene\nadduct (<b>3</b>) and an <b>I</b><i>i</i><b>Pr</b>-arsaketene complex (<b>4</b>), respectively. Furthermore,\nthe related reactions of precursor <b>1</b> with sodium phosphaethynolate\nyield both a stibanyl-phosphaketene (<b>5</b>) and a stibanyl-functionalized <b>I</b><i>i</i><b>Pr</b>-phosphaketene adduct (<b>6</b>).