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diphenyl ether

n. (lb en organic compound) The aromatic ether (C6H5)2O

Wikipedia
Diphenyl ether

Diphenyl ether is the organic compound with the formula O( C H). The molecule is subject to reactions typical of other phenyl rings, including hydroxylation, nitration, halogenation, sulfonation, and Friedel–Crafts alkylation or acylation. This simple diaryl ether enjoys a variety of niche applications.