TY - JOUR
T1 - MgLa mixed oxides as highly active and selective heterogeneous catalysts for Wadsworth-Emmons reactions
AU - Kantam, M. L.
AU - Kochkar, H.
AU - Clacens, J. M.
AU - Veldurthy, B.
AU - Garcia-Ruiz, A.
AU - Figueras, F.
N1 - Funding Information:
M.L.K thanks CNRS for a fellowship at IRC, and A.G-R thanks CONACYT de Mexico for a sabbatical grant.
PY - 2005/2/10
Y1 - 2005/2/10
N2 - The Wadsworth-Emmons reaction usually run in a stoichiometric mode with a high ratio base/substrate can be achieved catalytically, minimizing the by-products. Diethyl(cyanomethyl)-phosphonate and triethylphosphonoacetate were reacted with different aldehydes on solid bases in batch conditions at 383 K. MgLa mixed oxide was found to be an efficient solid base for the selective synthesis of α-, β-unsaturated esters and nitriles with greater than 80% yields, and avoiding Knoevenagel condensation and aldolisation even with aliphatic aldehydes. The catalyst could be recycled once with high activity. The effect of substituents on phenyl ring proves that the reaction proceeds via a base catalysed mechanism with a low charge on intermediate species.
AB - The Wadsworth-Emmons reaction usually run in a stoichiometric mode with a high ratio base/substrate can be achieved catalytically, minimizing the by-products. Diethyl(cyanomethyl)-phosphonate and triethylphosphonoacetate were reacted with different aldehydes on solid bases in batch conditions at 383 K. MgLa mixed oxide was found to be an efficient solid base for the selective synthesis of α-, β-unsaturated esters and nitriles with greater than 80% yields, and avoiding Knoevenagel condensation and aldolisation even with aliphatic aldehydes. The catalyst could be recycled once with high activity. The effect of substituents on phenyl ring proves that the reaction proceeds via a base catalysed mechanism with a low charge on intermediate species.
KW - Activated hydrotalcites
KW - Catalysis by solid bases
KW - Fluorinated hydrotalcite
KW - MgLa mixed oxides
KW - Wadsworth-Emmons reaction
UR - http://www.scopus.com/inward/record.url?scp=11844281524&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2004.07.014
DO - 10.1016/j.apcatb.2004.07.014
M3 - Artículo
SN - 0926-3373
VL - 55
SP - 177
EP - 183
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
IS - 3
ER -