IONIC LIQUID-PHASE ORGANIC SYNTHESIS (IOLIPOS) METHODOLOGY
373
purified by chromatography on silica gel using methyl-
ene chloride as eluent (Rf 0.65). The enantiomeric
excess for VIa (ee = 47%) was determined by chiral
HPLC.
(J = 126 Hz), 62.8 t (J = 151 Hz), 68.9 d (J = 145 Hz),
122.9 d.m (J = 203 Hz), 123.9 d.m (J = 202 Hz),
125.8 d.m (J = 160 Hz), 129.4 d.d (J = 163, 6 Hz),
150.9 d.m (J = 223 Hz), 165.2 s (C=O), 178.2 s (C=O).
High-resolution mass spectrum: m/z 317.1501 [M]+.
C17H21N2O4. Calculated: M 317.1499.
To conclude, a novel approach to cross aldol reac-
tion has been developed on the basis of ionic liquid-
phase strategy with a generic protocol including cou-
pling reaction, detachment, and purification. The main
advantage of the ionic liquid-phase organic synthesis
(IoLiPOS) methodology is that the structure of each
intermediate could be verified by spectroscopic meth-
ods. To our knowledge, preliminary results of this
cross aldol reaction supported on ILPs have never been
reported, and they may be a complement to those
existing in the literature and involving IL as recyclable
solvent [13], conventional homogeneous solution
organic synthesis [14], or IL-supported catalyst [15].
Further developments of this aldol reaction supported
on ionic liquid-phases are currently under investiga-
tion, and the results will be reported elsewhere.
H. Hakkou thanks the Economic European Com-
munity (EEC) for a research fellowship (contract
no. G5RD-CT 2001-00546).
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RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 3 2011