作者:Jorge D. Mufato、Daniel R. Vega、José M. Aguirre、Diego J. de la Faba、Beatriz Lantaño
DOI:10.1016/j.molstruc.2010.12.005
日期:2011.2
In this work only one diastereomer of benzamarone (1,2,3,4,5-pentaphenylpentan-1,5-dione) 1 was isolated from tandem condensation/addition reaction between deoxybenzoin and benzaldehyde in alkaline medium and by Michael addition of deoxybenzoin to (E)-2-phenylchalcone. Compound 1 was investigated by single crystal X-ray diffraction: C35H28O2, Mr = 480.57, triclinic system, space group P1 with unit cell parameters a = 11.489(2), b = 11.669(2), c = 11.855(2) angstrom, alpha = 104.31(4), beta = 116.91(3), gamma = 98.96(3)degrees, V = 1305.6(4) angstrom(3), Z = 2, T = 25(2) degrees C, rho(calc) = 1.222 gr/cm(3), mu = 0.074 mm(-1). This study allowed us to assign the configuration 2R,4R/25.4S corresponding to the diastereomer racemate C (Fig. 1) due to the fact that the crystal structure exhibits two independent molecules in the unit cell. Data obtained using NMR spectroscopy [1D and 20 NMR] are agreement with those obtained by X-ray diffraction. By comparison of NMR data, the configuration corresponding to the diastereomer racemate C was assigned to other substituted benzamarones synthesized by us, which present two and three stereocenters in their structure. (C) 2010 Elsevier B.V. All rights reserved.