Beschreibung:
<jats:p>In the title compound, C<jats:sub>18</jats:sub>H<jats:sub>23</jats:sub>O<jats:sub>4</jats:sub>P, the dihedral angle between the aromatic ring planes is 69.94 (14)°. Both ethyl side chains are disordered over two sets of sites, with occupancy ratios of 80:20 and 70:30. In the crystal, inversion dimers linked by pairs of O—H...O hydrogen bonds occur, leading to<jats:italic>R</jats:italic><jats:sub>2</jats:sub><jats:sup>1</jats:sup>(8) loops, and C—H...O and weak C—H...π interactions are also seen.</jats:p>