Construction Of The Chiral Spiro-oxindoles Through Asymmetric Organocatalysis And Asymmetric Hydrogenation Of Ketones With A Chiral Cationic Ruthenium Diamine Catalyst

This dissertation includes two aspects of research works. The first part is the construction of the spiro-oxindoles through organocatalysis and the second part is the asymmetric hydrogenation of ketones with a chiral cationic ruthenium diamine catalyst.In the first part of this dissertation, some chiral organocatalysts including J?rgensen-Hayashi catalyst and bifunctional thiourea catalyst were prepared with proline and cinchona alkaloid as starting materials according to the reported procedures. The domino Michael-Aldol reactions of isatin derived alkenes with pentane-1,5-dial and Michael-cyclization-tautomerization reactions of isatylidene malononitriles with α, α-dicyanoalkenes were catalyzed by these organocatalysts, respectively. And a series of multi-stereogenic spiro cyclohexaneoxindoles and spiro oxindole diene derivatives have been obtained in good yields with moderate diastereoselectivities and excellent enantioselectivities.In the second part of this dissertation, an efficient methodology for the asymmetric hydrogenation of ketones catalyzed by the phosphine-free η6-p-arene/Ts DPEN-Ru(II) complex was developed. A wide range of chiral β-hydroxysulfonamides, β-hydroxysulfones, bis(β-hydroxy) sulfones and hydrobenzoins were obtained in high yields and excellent enantioselectivities. The cascade asymmetric hydrogenation/ dynamic kinetic resolution(DKR) of cyclic β-ketosulfonamides and β-ketosulfones was also studied, which afforded the corresponding chiral β-hydroxylsulfonamides and β-hydroxylsulfones in high yields with excellent enantioselectivities and diastereoselectivities.