Ruthenium-catalyzed dynamic kinetic resolution

Box 9.1 Utility of the ruthenium-catalyzed dynamic kinetic resolution... 

Kim, M. J., Choi, Y. K., Choi, M. Y., Kim, M. and Park, J. (2001). Lipase/ruthenium-catalyzed dynamic kinetic resolution of hydroxy acids, diols, and hydroxy aldehydes protected with a bulky group.. Org. Chem., 66,4736-4738. 

Scheme 5.11 Dynamic kinetic resolution of alcohol 18 by combination of enzymatic transesterification and ruthenium-catalyzed racemization.

Dynamic kinetic resolution is an excellent methodology to prepare enantiomeri-cally pure compounds and, in this context, chiral 4-(dimethylammo)pyridine (DMAP) iron and ruthenium " complexes have been reported to catalyze the... 

Dijksman, A. Elzinga, M., J. Li, Yu-Xin, Arends, I., Sheldon, R., A. Efficient ruthenium-catalyzed racemization of secondary alcohols application to dynamic kinetic resolution. Tetrahedron Asymmetry 2002, 13, 879-884. 

V Ratovelomanana-Vidal, J.-P. Genet, Synthetic Applications of the Ruthenium-Catalyzed Hydrogenation via Dynamic Kinetic Resolution, Can. J. Chem. 2000, 78, 846-851. 

It is worth mentioning the emergence of sequential catalytic processes involving a ruthenium-catalyzed step followed by a catalytic enzymatic transformation. This strategy has been developed by the groups of J.E. Backvall, and M.-J. Kim and J. Park especially for the dynamic kinetic resolution of alcohols (Scheme 50) [107-109]. 

Ratovelomanana-Vidal, V., Genet, J.-P. Synthetic applications of the ruthenium-catalyzed hydrogenation via dynamic kinetic resolution. 

Kitamura, M., Tokunaga, M., Noyori, R. Quantitative expression of dynamic kinetic resolution of chirally labile enantiomers stereoselective hydrogenation of 2-substituted 3-oxo carboxylic esters catalyzed by BINAP-ruthenium(ll) complexes. J. Am. Chem. Soc. 1993,115, 144-152. 

Scheme 19.5 Dynamic kinetic resolution of a secondary alcohol based on ruthenium-catalyzed racemization and enzymatic acylation.

Bai W-J, Xie J-H, Li Y-L, Liu S, Zhou Q-L. Enantioselective synthesis of chiral (3-aryloxy alcohols by ruthenium-catalyzed ketone hydrogenation via dynamic kinetic resolution (DKR). Adv. Synth. Catal 2010 352(l) 81-84. 

Dynamic Kinetic Resolution (DKR) under Hydrogenation Conditions Ruthenium-catalyzed asymmetric hydrogenation of racemic a-substituted ketones via-dynamic kinetic resolution (DKR) is one of the elegant and powerful methods for the synthesis of chiral alcohols that simultaneously control two adjacent stereogenic centers with high levels of selectivity in a single chemical operation. This method was first reported... 

Genet JP, Pinel C, Mallart S, Juge S, Thorimbert S, Laffitte JA. Asymmetric synthesis. Practical production of D and L threonine. Dynamic kinetic resolution in rhodium and ruthenium catalyzed hydrogenation of 2-acylamino-3-oxobuty-rates. Tetrahedron Asymm. 1991 2(7) 555-567. 

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