Copper(I) Oxide

[1317-39-1] Cu2O (MW 143.08) InChI = 1S/2Cu.O InChIKey = BERDEBHAJNAUOM-UHFFFAOYSA-N (weak base; activates halides towards nucleophilic substitution;1 forms carbenoid intermediates from diazo compounds2 and radicals from arenediazonium salts;3 activates isocyanides towards 1,1-addition4) Physical Data: mp 1235 °C; d ∼6 g cm−3. Solubility: insol most organic solvents; slightly sol quinoline and benzonitrile;1a variously sol acids (salt formation, in some cases disproportionation to Cu0 and CuII). Form Supplied in: red to brown powder; widely available. Typical impurities: Cu, CuO,5 NaCl,5 stabilizers (e.g. gelatine,5 oil, zinc stearate), moisture.5 For reactions in anhydrous media the reagent is vacuum-dried before use. Preparative Methods: since reactions involving Cu2O are heterogeneous, they may critically depend on the particle size.6b An active preparation is obtained by reduction of CuII solutions7 but may suffer deactivation at high reaction temperatures1a octahedral,54 cubic,55, 56 thread/wire,56 tube/rod,57 crystalline,58 amorphous,59 or poly(vinyl alcohol) coated60 nanoparticles can be prepared. Handling, Storage, and Precautions: Cu2O is incompatible with alkynes, diazonium salts, and diazo compounds. Copper compounds are moderately toxic.