Selective dimerization of aldehydes to esters catalyzed by zirconocene and hafnocene complexes

Lanthanide Formamidinates as Improved Catalysts for the Tishchenko Reaction

“…The use of the standard aluminum catalyst Al(OiPr) 3 [21,22] under the reaction conditions described above led to a low yield of product ( [33] or other aluminum-based catalysts (Table 1, Entry 13) [34] did not reach the level of activity of the lanthanum compounds. All classical transition-metal catalysts, [23][24][25] as well as boric acid [22] ( Table 1, Entries 14-18), failed to catalyze the reaction to complete conversion. Some more recent examples from transition-metal chemistry show high yields, but are still slower than the lanthanide systems (Table 1, Entry 19).…”

“…More recently, other catalysts such as boric acid [23] and a few transition-metal complexes have been used. [24][25][26] However, these alternative catalysts are either only reactive under extreme reaction conditions (e.g. boric acid) or they are slow (e.g.…”

“…boric acid) or they are slow (e.g. [(C 5 H 5 ) 2 ZrH 2 ]), [24] expensive (e.g. [H 2 Ru(PPh 3 ) 2 ]), [25] or give low yields (e.g.…”

Monoalcoholates of 1,3-diols as effective catalysts in the Tishchenko esterification of 1,3-dioxan-4-ols

“…2 The reaction has been carried out with a number of other catalysts such as ruthenium complexes, 3 alkali earth metal oxides, 4 boric acid, 5 sodium alkoxides 6 (with aryl aldehydes), alkali metals, 7 zirconocenes, 8 and lanthanide (amide) complexes. 9 The mechanism of the Tishchenko reaction involves a hydride shift.…”

Synthesis and Crystal Structure of Tris(1,3-diphenyl-1,3-propanedionato)Titanium(III)

“…[4][5][6] Recently, we have investigated the reactivities of [Cp 2 M] (M=Ti, Zr) 7,8 prepared from [Cp 2 TiM] and 2n-BuLi with β-diketone. Synthesis and structural properties of Ti(III)(acac) 3 , 9 cisCpZr(acac) 2 Cl, 10 Cp 2 (1-phenyl-1,3-butanedionato)Ti(III) and Cp 2 (1,3-diphenyl-1,3-propanedionato)Ti(III) 11 have been reported.…”