title: Crystal structure of ethyl 2-(di-eth-oxy-phosphor-yl)-2-(2,3,4-tri-meth-oxy-phen-yl)acetate.
abstract: The title compound, C17H27O8P, was prepared by Michaelis-Arbuzov reaction of ethyl 2-bromo-2-(2,3,4-tri-meth-oxy-phen-yl)acetate and triethyl phosphite. Such compounds rarely crystallize, but single crystals were recovered after the initial oil was left for approximately 10 years. The bond angle of the sp (3)-hybridized C atom connecting the benzene derivative with the phospho unit is widened marginally [112.5 (2)°]. The terminal P-O bond length of 1.464 (2) Å clearly indicates a double bond, whereas the two O atoms of the eth-oxy groups connected to the phospho-rous atom have bond lengths of 1.580 (2) Å and 1.581 (3) Å. The three meth-oxy groups emerge out of the benzene-ring plane due to steric hindrance [C-C-O-C torsion angles = -179.9 (3)°, -52.9 (4)° and 115.3 (4)°]. In the crystal, inversion dimers linked by pairs of C-H⋯O=P hydrogen bonds generate R 2 (2)(14) loops. The chosen crystal was modelled as a non-merohedral twin.
authors.affiliation: Johannes Gutenberg-Universität Mainz, Institut für Organische Chemie, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Schubert
authors.affiliation: Johannes Gutenberg-Universität Mainz, Institut für Organische Chemie, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Schollmeyer
authors.affiliation: Johannes Gutenberg-Universität Mainz, Institut für Organische Chemie, Duesbergweg 10-14, 55128 Mainz, Germany.
authors.forename: Siegfried R
authors.initials: SR
authors.lastname: Waldvogel
keywords: Michaelis–Arbuzov reaction; crystal structure; hydrogen bonds; non-merohedral twin; phosphonoacetate