Bis(tricyclohexylphosphine)nickel(II) chloride, with CAS number 19999-87-2, is a nickel(II) complex coordinated by two bulky tricyclohexylphosphine ligands and two chloride anions. It is a stable, air-sensitive, crystalline solid commonly used as a pre-catalyst or catalyst precursor in a wide range of cross-coupling reactions, including Suzuki, Negishi, and Kumada couplings. Its primary application is in synthetic organic chemistry, where it serves as an efficient and versatile nickel-based catalyst for forming carbon-carbon and carbon-heteroatom bonds, often offering a cost-effective alternative to palladium catalysts. The compound is also utilized in various other catalytic transformations such as hydrogenation and oligomerization. Due to its specific role as a metal catalyst and its broad utility in organic synthesis, it is best classified under the catalyst and ligand categories within synthetic chemistry.