Chiral ferrocenyl diphosphines for asymmetric transfer hydrogenation of acetophenone

Abstract

To cite this version:Jérôme Cabou, Jacques Brocard, Lydie Pélinski. Chiral ferrocenyl diphosphines for asymmetric transfer hydrogenation of acetophenone. Tetrahedron Letters, Elsevier, 2005, 46, pp

P‐Stereogenic Ferrocene‐Based (Trifluoromethyl)phosphanes: Synthesis, Structure, Coordination Properties and Catalysis

“…All attempts to separate the diastereoisomers, even by means of HPLC proved fruitless. Diphenylphosphane analogue 6 was obtained in a moderate yield of 68 %, and was transformed into the known bis(phosphane) 3 upon treatment with diphenylphosphane in acetic acid at elevated temperature (72 %) 14. However, no formation of the methyl analogue 2 was observed under these conditions.…”

Selective Syntheses of Planar-Chiral Ferrocenes

“…94,140,199−203 The introduction of a nucleophile at the α carbon is usually achieved by starting from the corresponding acetate, which is quantitatively accessible upon treatment of the tertiary amine with excess acetic anhydride or, more conveniently, directly from the amine in glacial acetic acid. In this way, the NMe 2 moiety has been replaced by ammonia and primary and secondary amines 74,128,129,131,134,135,137,148,155,158,197,204,205 as well as phosphines, 74,138,147,157,172,181,183,184,193,196,198,206 including heterocyclic species, 87,128,129,140,141,146,154,179,184,185,190,207−210 azides for 1,3-dipolar cycloadditions, 166 carbon nucleophiles, 84,85,143 alcohols, 74,76 and thioles 147,161,211 as well as carboxylates 125,130,142,177 and thiocarboxylates, 132 giving upon hydrolysis the corresponding alcohols or thioles. Primary and secondary a m i n e s o b t a i n e d c a n b e t r a n s f o r m e d i n t o imines, 89,[91][92][93]…”

“…2- or 2,1′-dilithiated ferrocenes derived from Ugi’s amine or related compounds have been treated with a wide range of electrophiles, giving phosphines, − ,− ,− ,− alcoholes and thioles, , aldehydes, − carboxylic acids and derivatives thereof (e.g., imines, oxazolines, esters, or amides), − thio- and selenoethers, ,,,,− and dithiocarbamates . Furthermore, transition-metal-mediated homo- and cross-coupling reactions have been performed with derived 2-halo- and 2-lithioferrocenes, furnishing aryl- and alkynyl-substituted ferrocenes − as well as biferrocenes. − In addition, diferr...…”

“…The introduction of a nucleophile at the α carbon is usually achieved by starting from the corresponding acetate, which is quantitatively accessible upon treatment of the tertiary amine with excess acetic anhydride or, more conveniently, directly from the amine in glacial acetic acid. In this way, the NMe 2 moiety has been replaced by ammonia and primary and secondary amines ,,,,,,,,,,,, as well as phosphines, ,,,,,,,,,,, including heterocyclic species, ,,,,,,,,,,,− azides for 1,3-dipolar cycloadditions, carbon nucleophiles, ,, alcohols, , and thioles ,, as well as carboxylates ,,, and thiocarboxylates, giving upon hydrolysis the corresponding alcohols or thioles. Primary and secondary amines obtained can be transformed into imines, ,− ,,,,, amidines, , and amides upon treatment with carbaldehydes/ketones, formamides, or acid chlorides/anhydrides.…”

Asymmetric transfer hydrogenation of prochiral ketones in aqueous media with chiral water‐soluble and heterogenized bifunctional catalysts of the RhCp*‐type ligand

“…Since this discovery, a significant number of new ligands have been reported for the ATH with ruthenium(II), iridium(III), and rhodium(III) complexes as catalysts in the ATH of ketones 18–35. More importantly, the hydride source for the reaction has been changed from isopropanol/KOH or HCOOH/NEt 3 to a “greener” hydride source using sodium formate/water, a solvent system that is readily available, benign, and environmentally acceptable 36–51.…”