250684-48-1Relevant academic research and scientific papers
Synthesis, properties and applications of BICAP: A new family of carbazole-based diphosphine ligands
Botman, Peter N. M.,Fraanje, Jan,Goubitz, Kees,Peschar, Rene,Verhoeven, Jan W.,Van Maarseveen, Jan H.,Hiemstra, Henk
, p. 743 - 754 (2007/10/03)
A new family of bidentate phosphine ligands based on the biscarbazole backbone has been synthesized and applied in the ruthenium- and rhodium-catalyzed asymmetric hydrogenations of methyl acetoacetate and dimethyl itaconate. The nitrogen atoms in these BICAP ligands allow facile introduction of substituents providing structurally similar, but electronically different ligands, which were used to fine-tune these reactions to 98% and 55% ee, respectively.
Synthesis of the dibenzofuran-based diphosphine ligand BIFAP and its water-soluble derivative BIFAPS and their use in ruthenium-catalyzed asymmetric hydrogenation
Gelpke, Arjan E. Sollewijn,Kooijman, Huub,Spek, Anthony L.,Hiemstra, Henk
, p. 2472 - 2482 (2007/10/03)
The syntheses of both enantiomers of the novel diphosphine ligand 2,2′-bis(diphenylphosphanyl)-1,1′-bidibenzofuranyl (BIFAP, 1) and the water-soluble analogue (-)-2,2′-bis(diphenylphosphanyl)-1,1′-bidibenzofuranyl-8,8′- disulfonic acid dipotassium salt (BIFAPS, 2) are reported. Advantage is taken of the very high regioselectivity in ring functionalisation of the 1,1′-bidibenzofuranyl backbone. These ligands are used in the ruthenium-catalysed hydrogenation of methyl acetoacetate and (Z)-acetamidocinnamic acid in methanol and water. In methanol both BIFAP and BIFAPS give the products in very high enantiomeric excess. With BIFAPS in water a slight drop in the ee of the products is observed. When BIFAPS is used with either water or methanol as the solvent the addition of a small amount of acid turns out to be essential for a fast reaction and high asymmetric induction.
