TY - JOUR
T1 - Lanthanide formamidinates as improved catalysts for the Tishchenko reaction
AU - Agustino, null
AU - Roesky, Peter W.
AU - Deacon, Glen B.
AU - Konstas, Kristina
AU - Junk, Peter C.
PY - 2008
Y1 - 2008
N2 - The tris(formamidinato)lanthanum(III) complexes [La(o-TolForm) 3(thf)2] [1; o-TolForm = N,N′-bis(o-tolyl) formamidin-ate], [La(XylForm)3(thf)] [2; XylForm = N,N′-bis(2,6-dimethylphenyl)formamidinate], and [La(EtForm)3] [3, EtForm = N,N′-bis(2,6-diethylphenyl)formamidinate] are a new class of precatalysts for the Tishchenko reaction. Their catalytic activity is a result of their high Lewis acidity and the ease with which the ligand spheres can be interchanged. For the dimerization of benzaldehyde to give benzyl benzoate, which is a benchmark reaction, compound 1 is, to the best of our knowledge, the most active catalyst ever reported. On a preparative scale, the reaction can be performed in the absence of solvent. A range of aromatic, heteroaromatic, and aliphatic aldehydes was rapidly converted into the corresponding esters by using catalysts 1-3.
AB - The tris(formamidinato)lanthanum(III) complexes [La(o-TolForm) 3(thf)2] [1; o-TolForm = N,N′-bis(o-tolyl) formamidin-ate], [La(XylForm)3(thf)] [2; XylForm = N,N′-bis(2,6-dimethylphenyl)formamidinate], and [La(EtForm)3] [3, EtForm = N,N′-bis(2,6-diethylphenyl)formamidinate] are a new class of precatalysts for the Tishchenko reaction. Their catalytic activity is a result of their high Lewis acidity and the ease with which the ligand spheres can be interchanged. For the dimerization of benzaldehyde to give benzyl benzoate, which is a benchmark reaction, compound 1 is, to the best of our knowledge, the most active catalyst ever reported. On a preparative scale, the reaction can be performed in the absence of solvent. A range of aromatic, heteroaromatic, and aliphatic aldehydes was rapidly converted into the corresponding esters by using catalysts 1-3.
KW - Aldehydes
KW - Homogeneous catalysis
KW - Lanthanum
KW - N ligands
KW - Rare-earth formamidinates
UR - http://www.scopus.com/inward/record.url?scp=38949157701&partnerID=8YFLogxK
U2 - 10.1002/ejoc.200700827
DO - 10.1002/ejoc.200700827
M3 - Article
AN - SCOPUS:38949157701
SN - 1434-193X
SP - 693
EP - 697
JO - European Journal of Organic Chemistry
JF - European Journal of Organic Chemistry
IS - 4
ER -