CaOPh2

CaOPh2, commonly written Ca(OPh)2, is a calcium(II) phenoxide—a metal alkoxide in which calcium is coordinated by two phenoxide (OPh) ligands. It is typically a white to off-white solid that is insoluble in water and many common organic solvents, but can dissolve in donor solvents such as tetrahydrofuran (THF) or diethyl ether, forming solvated species.

Preparation of Ca(OPh)2 can be achieved by salt metathesis or by direct reaction of a calcium oxide source with phenol. A representative route is CaCl2 + 2 NaOPh → Ca(OPh)2 + 2 NaCl, performed in a polar aprotic solvent. Alternatively, CaO + 2 PhOH → Ca(OPh)2 + H2O provides a direct entry from calcium oxide and phenol, though moisture sensitivity must be managed during handling.

In the solid state, calcium(II) phenoxides like Ca(OPh)2 often form polymeric networks with bridging phenoxide ligands, leading to coordination environments around calcium that are typically 6- to 7-coordinate. The exact structure can vary with the crystal form and degree of solvation; discrete monomeric units are less common.

Reactivity is strongly influenced by air and moisture; Ca(OPh)2 hydrolyzes upon exposure to moisture to yield calcium hydroxide and phenol. In solution, it can act as a precursor to other calcium-phenoxide complexes and can serve as a reagent for introducing phenoxide ligands in inorganic synthesis and materials chemistry, including the preparation of coordination polymers and related catalysts.

Safety considerations include moisture sensitivity and hydrolysis products. Handle Ca(OPh)2 under inert atmosphere and dry conditions to avoid degradation; phenol and calcium hydroxide formed on hydrolysis require appropriate disposal and ventilation.