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Updated: Jul 15, 2026
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Differences in the crystal structures of two dialkyl diester triphenylphosphonium ylids
Fernando Castañeda1, Carolina Jullian, Clifford A Bunton
1Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Casilla 233, Santiago, Chile. fcastane@ciq.uchile.cl
Abstract:
Hydrogen bonding and crystal packing play major roles in determining the conformations of ethyl methyl 2-(triphenylphosphoranylidene)malonate, Ph(3)P=C(CO(2)CH(3))CO(2)CH(2)CH(3) or C(24)H(23)O(4)P, (I), and dimethyl 2-(triphenylphosphoranylidene)malonate, Ph(3)P=C(CO(2)CH(3))(2) or C(23)H(21)O(4)P, (II). In (I), the acyl O atom of the ethyl ester group is anti to the P atom, while the O atom of the methyl ester group is syn. In (II), the dimethyl diester is a 1:1 mixture of anti-anti and syn-anti conformers.
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