Palladium-catalyzed transfer hydrogenation in alkaline aqueous medium

pH‐Dependent Catalytic Activity and Chemoselectivity in Transfer Hydrogenation Catalyzed by Iridium Complex with 4,4′‐Dihydroxy‐2,2′‐bipyridine

“…[26] On the other hand, attempts have been made at the chemoselective TH of a,b-unsaturated carbonyl compounds in iPrOH. [27][28][29][30][31] The pH-dependent chemoselective TH of a,b-unsaturated carbonyl compounds in an aqueous formate solution was reported by Frost for the first time in 2007. [32] However, further improvements in catalyst efficiency, selectivity, and versatility are required.…”

“…13–20 Although highly efficient TH catalysts in i PrOH have been reported recently,21–25 aqueous TH reactions, which usually require high reaction temperatures and low substrate/catalyst (S/C) ratios, seem to be sluggish except for an iridium complex with monotosylated ethylenediamine (turnover frequency (TOF) up to 132 000 h −1 at 80 °C) 26. On the other hand, attempts have been made at the chemoselective TH of α,β‐unsaturated carbonyl compounds in i PrOH 27–31. The pH‐dependent chemoselective TH of α,β‐unsaturated carbonyl compounds in an aqueous formate solution was reported by Frost for the first time in 2007 32.…”

Synthesis and catalytic activity of perfluoroalkylated pyridine–palladium(II) complex toward olefin hydrogenation in scCO2 and conventional organic solvents

“…The modified palladium complexes with nitrogen containing bases (pyridine, ethylene diamine, quinoline) allows preparing of highly selective catalyst for alkynes and conjugated diene hydrogenation [7,8], enantio selective hydrogenation of ␣,␤-unsaturated acid derivatives [9,10], chemoselective hydrogenation of unsaturated ketones and aldehydes [11,12]. Catalyst decomposition and poor reproducibility of the reaction was the major disadvantages of these catalytic systems in organic solvents.…”

Highly active and selective catalysts of hydrogenation based on palladium bis-acetylacetonate and phenylphosphine

“…Among VIII group of transition metals the palladium-based catalysts for hydrogenation are of special interest [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. The modification of palladium by nitrogen-containing bases (quinoline, ethylendiamine, pyridine), as well as alkaloids allows preparing of highly selective catalysts for alkyne and conjugated diene hydrogenation [1][2][3], chemoselective hydrogenation of unsaturated aldehydes and ketones [7,8], enantioselective hydrogenation of ␣,␤-unsaturated acid derivatives, etc.…”

“…The modification of palladium by nitrogen-containing bases (quinoline, ethylendiamine, pyridine), as well as alkaloids allows preparing of highly selective catalysts for alkyne and conjugated diene hydrogenation [1][2][3], chemoselective hydrogenation of unsaturated aldehydes and ketones [7,8], enantioselective hydrogenation of ␣,␤-unsaturated acid derivatives, etc. [2,3,9,10]. Along with studies of the Pd supported heterogeneous catalysts as well as developing chemistry of Pd nanoclusters [5,6,11,12], determination of mechanistic formation and activity nature of Pd complex catalysts with phosphine ligands is in progress [13][14][15][16][17].…”