BINAP hydrogen incorporation

Benzamido-cinnamic acid, 20, 38, 353 Benzofuran polymerization, 181 Benzoin condensation, 326 Benzomorphans, 37 Benzycinchoninium bromide, 334 Benzycinchoninium chloride, 334, 338 Bifiinctional catalysts, 328 Bifiinctional ketones, enantioselectivity, 66 BINAP allylation, 194 allylic alcohols, 46 axial chirality, 18 complex catalysts, 47 cyclic substrates, 115, 117 double hydrogenation, 72 Heck reaction, 191 hydrogen incorporation, 51 hydrogen shift, 100 hydrogenation, 18, 28, 57, 309 hydrosilylation, 126 inclusion complexes, oxides, 97 ligands, 19, 105 molecular structure, 50, 115 mono- and bis-complexes, 106 NMR spectra, 105 olefin isomerization, 96... 

SCHEME 39. Pattern of hydrogenation incorporation in BINAP-Ru(II)-catalyzed hydrogenation. 

The results of deuterium labeling experiments shown in Scheme 37 clearly show the operation of a monohydride mechanism in the BINAP-RuOI) catalyzed hydrogenation of unsaturated carboxylic acids. However, with many olefinic substrates with a neutral, rather than anionic, secondary binding site, the products exhibit a similar degree of isotope incorporation at the two hydrogenated centers (Scheme 39). The out-... 

Another Ru(BINAP)-catalyzed asymmetric hydrogenation that has been performed at manufacturing scale involves the reduction of a functionalized ketone. The reduction of hydroxyacetone catalyzed by [NH2Et2]+[ RuCl(p-tol-BINAP) 2 (li-CI)3 (39) proceeds in 94% ee (Scheme 12.11).46 The chiral diol (40) is incorporated into the synthesis of levofloxacin (41), a quinolinecarboxylic acid that exhibits marked antibacterial activity. Current production of 40 is 40 tons per year by Takasago International Corp.46... 

Cyclopentadienyl groups can be incorporated in a manner similar to that shown in eqnation(4) for phosphines. Metallocene derivatives (see Metallocene Complexes),mtani, can be incorporated into these modified polymers. Also, chiral phosphines such as DIOP and BINAP have been immobilized on polymers to be used in asyimnetric hydrogenation catalysis and related reactions. ... 

The minor R enantiomer is also produced via the same, but diastereomorphic, reaction path vay as proved by a detailed analysis of isotope incorporation patterns of both enantiomeric products. The enantioselectivity is determined at the first irreversible hydrogenolysis step, but practically at the formation of the cat/sub complexes 18s and 18j e. 18s is unfavored because of the existence of steric repulsion between alkoxycarbonyl group in the substrate and one of benzene rings on P atom of BINAP-Ru catalyst. In contrast to the Rh-catalyzed hydrogenation where the minor... 

The invention of Ru-binap dicarboxylate complexes extends the scope of asymmetric hydrogenations . Simple acyclic acids are hydrogenated with enantioselectivities from 80 to 100%. The procedure is applicable to /3,y-unsaturated carboxylic acids with about 80% e.e. . Deuterium incorporation indicates that a mechanism involving a metal monohydride complex operates. An amino group on the chiral phosphine ligand enhances the efficacy of ferrocenylphosphine-Rh complexes toward trisubstituted acyclic acids . 

Pu [23] prepared soluble irregular copolymers, and Fan [24] regular ones (9), of BINAP and BINOL that were incorporated into the polymer chain [Eq. (7)]. The ruthenium complexes were used for catalytic hydrogenation of arylacrylic acid [Eq. (8)]. The maximum ee of 88% (er= 16) with TTN = 100 is lower than with BINAP imder comparable conditions. No recycling of the hydrogenation catalyst is reported, whereas for diethylzinc addition to benzaldehyde the catalyst was recycled by precipitation with methanol. 

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