BINAP polymer-bound

Fig. 32.35 Hydrogenation of I -acetonaphthone with the polymer-bound BINAP/DPEN-Ru catalyst.

The homogeneous chiral phosphine/DPEN-Ru catalyst can be immobilized by use of polymer-bound phosphines such as polystyrene-anchored BINAP (APB-BINAP) [57, 98], Poly-Nap [99], and poly(BINOL-BINAP) [100], poly(BINAP) [101]. These complexes hydrogenate T-acetonaphthone and acetophenone with S/C of 1000-10 000 under 8 10 atm H2 to give the corresponding secondary alcohols in 84-98% e.e. The recovered complexes are repeatedly used without significant loss of reactivity and enantioselectivity. Immobilization allows the easy separation of catalyst from reaction mixture, recovery, and reuse. These advantages attract much attention in combinatorial synthesis. 

Bis(aminomethyl)-BINAP is a precursor of a polymer-bound ligand. ... 

Close to polymer boimd-BINAP/diamine ruthenium precatalyst [11], complexes of BINAP or their derivatives in the presence of polymer bound diamine have been employed. These catalytic systems have been mainly studied by Itsuno with immobilized diphenylethylenediamine (DPEN). As the use of A-substituted 1,2-diamine ligands decreased the catalytic activity of hydrogenation of simple ketones contrary to free diamine ligands, they have been less employed. However, A-substitnted 1,2-diamine ligands are rather effective in the hydrogenation of a-snbstitnted ketone, snch as a-amido ketones. Thus, two types of immobilized DPEN have been performed. Fnnctionalized DPEN for subsequent grafting onto polymer or eopolymerization are presented (Scheme 3). 

The heterofunctionalization of haloarenes on a solid support is a versatile method to create smaU-molecule libraries of high diversity. Starting with simple resins, aryl amines can be prepared in good to excellent yield by amination of polymer-bound aryl halides employing either the Hartwig or the Buchwald protocol (BINAP or P(o-Tol)3, t-BuONa (Scheme 16) for a review see Ref. Primary and secondary alkylamines... 

---