Preparation of Novel Chiral Ligands from Natural Sugars and Their Application to Catalytic Asymmetric Synthesis

2，3:4，6-di-ο-isopropylidene-α-D-glucopyranosyl-(1，1)-4，6-ο-isopropylidene-α-D-gluco-pyranoside(1)与α，α-海藻糖衍生的亲水性膦-亚膦或二亚膦配体的新型水溶性手性催化剂催化脱氢氨基酸或亚胺的高对映选择性氢化反应。(1)α衍生的膦-亚膦配体的水溶性手性铑催化剂的制备和甲基化反应。2，3:4，6-di-ο-isopropylidene-α-D-glcopyranosyl-(1，1)-4，6-ο-isopropylidener-2-(diphenyphosphi-no)-2-deoxy-3与α-海藻糖反应得到2，3-二ο-甲硫基二糖2，2，3-二氢二糖3，3-二氢二糖3，与KPPh_2开环得到3-羟基-2-二苯基膦衍生物4，4与Ph_2PCl反应得到-0-(二苯基膦)-α-D-吡喃葡萄糖苷(5)。最后，5与[Rh(Acac)(Cod)]反应，然后用HbF4水溶液处理，得到阳离子Rh…含六个游离基的更多的络合物6。(2)合成含亚膦配体的水溶性手性铱催化剂，1与Ph_2PCl反应得到2，3:4，6-di-ο-isopropylidene-α-D-glcopyranosyl-(1，1)-4，6-ο-isopropylidene-2，3-di-ο-(phenyphosphino)-α-D-altropyranoside(7)。7与[Ir(Acac)(CoD)]反应，然后用HbF_4水溶液处理，得到了含有6个自由羟基的阳离子Ir络合物8.(3)脱氢氨基酸及其酯在水或水/有机两相介质中的不对称氢化反应.标题化合物6是脱氢氨基酸及其酯在水或水/有机两相介质中生成(R)-α-氨基酸衍生物的有效催化剂.在两相体系中，催化剂被固定在水相中。因此，可以通过简单的相分离回收含催化剂的水通道相，并在加氢反应中重复使用，以得到几乎相同水平的加氢产物的对映体过量。(4)亚胺与8的不对称加氢反应标题化合物8可以作为催化剂用于几个亚胺的对映体选择性加氢，得到对映异构化的富仲胺。较少

We developed the highly enantioselective hydrogenation of dehydroamino acids or imines using novel water-soluble chiral rhodium and iridium catalysts bearing hydrophilic phosphine-phosphinite or diphosphinite ligand derived from α,α-trehalose.(1) Preparation of Water-soluble Chiral Rhodium Catalyst having Phosphine-phosphinite LigandMesylation of 2,3:4,6-di-ο-isopropylidene-α-D-glucopyranosyl-(1,1)-4,6-ο-isopropylidene-α-D-gluco-pyranoside (1) derived from α,α-trehalose with MsCl gave 2,3-di-ο-mesyl disaccharide 2. The treatment of 2 with NaOEt gave 2,3-anhydro disaccharide 3. The ring-opening of an epoxide moiety in 3 with KPPh_2 afforded 3-hydroxy-2-diphenylphosphino derivative 4. The reaction of 4 with Ph_2PCl gave 2,3:4,6-di-ο-isopropylidene-α-D-glcopyranosyl-(1,1)-4,6-ο-isopropylidener-2-(diphenyphosphi-no)-2-deoxy-3 -0-(diphenyl- phosphino)-α-D-altropyranoside (5). Finally, the reaction of 5 with [Rh(acac)(cod)] followed by treatment with aqueous HBF_4 afforded a cationic rhodium … More complex 6 bearing six free hydroxyl groups.(2) Preparation of Water-soluble Chiral Iridium Catalyst having Diphosphinite LigandReaction of 1 with Ph_2PCl gave 2,3:4,6-di-ο-isopropylidene-α-D-glcopyranosyl-(1,1)-4,6-ο-isopropylidene-2,3-di-ο-(phenyphosphino)-α-D-altropyranoside (7). The reaction of 7 with [Ir(acac)(cod)] followed by treatment with aqueous HBF_4 afforded a cationic iridium complex 8 bearing six free hydroxyl groups.(3) Asymmetric Hydrogenation of Dehydroamino Acids and their Esters with 6 in an Aqueous MediumThe title complex 6 was found to be an effective catalyst for enantioselective hydrogenation of dehydroamino acids and their esters leading to (R)-α-amino acid derivatives in water or an aqueous/organic biphasic medium. In the biphasic system, the catalyst is immobilized in the aqueous phase. Therefore, the aqueopus phase involving catalyst can be recovered by simple phase separation and reused for further operation in hydrogenation to give almost same level of enantiomeric excess of a hydrogenated product.(4) Asymmetric Hydrogenation of Imines with 8The title complex 8 can act as a catalyst for enantioselective hydrogenation of several imines to give enantiomericaly enriched secondery amines. Less