Tri­phenyl­phosphine oxide–1‐naphthoic acid (1/1)

In the title compound, C₁₈H₁₅OP·C₁₁H₈O₂, co‐crystallization of tri­phenyl­phosphine oxide with 1‐naphthoic acid yields a supramolecular structure held together by one O—H?O and three C—H?O hydrogen bonds. The O—H?O hydrogen bond O?O = 2.592 (2) Å] has little effect on the O=P bond distance.