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以(R)或(S)-H_8-BINOL为配体骨架,合成具有螺旋结构C_3对称的六个新型单齿亚磷酸酯配体,并将它们首次成功应用于Rh(acac)(CO)_2催化苯乙烯的不对称氢甲酰化,和Cu(OTf)_2催化二乙基锌对链烯酮的不对称1,4-共轭加成反应研究中.在铑催化苯乙烯的不对称氢甲酰化反应中,螺旋结构C_3对称的单齿亚磷酸酯配体给出高的催化活性(转化率93%)和支链醛/直链醛区域选择性(b/n=95/5),和较低的对映选择性[28%ee(R)].在铜催化二乙基锌对链烯酮的不对称1,4-共轭加成反应中,以查尔酮为底物筛选配体,优化反应条件;在优化的反应条件下,考察11种不同结构链状烯酮底物对反应的适应性;以Cu(OTf)_2作为催化剂前体,乙醚为溶剂,在-20℃,配体(R)-3中大位阻金刚烷基和(R)-H_8-联萘基团之间的空间结构匹配是获得98%分离产率和72%(R)对映选择性的关键因素,产物绝对构型主要由配体结构中H8-联萘基团的构型决定.研究结果证明C_3对称的新型单齿亚磷酸酯配体在不对称氢甲酰化和1,4-共轭加成反应中具有应用潜力.
Six novel monodentate phosphite ligands with C_3 symmetry of helix were synthesized using (R) or (S) -H_8-BINOL as ligand backbone and successfully applied to Rh (acac) (CO) _2 Asymmetric Hydroformylation of Styrene and Cu (OTf) _2 Catalyzed Asymmetric 1,4-Conjugated Addition of Diethylzinc to Alkenes Catalyzed by Asymmetric Hydrogenation of Styrene over Rhodium Formylation, monodentate phosphite ligands with symmetrical helix structure C_3 gave high catalytic activity (93% conversion) and branched chain aldehyde / straight chain aldehyde selectivity (b / n = 95/5) , And lower enantioselectivity [28% ee (R)] .In copper-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to alkenones, chalcone was used as a substrate The ligands were screened and the reaction conditions were optimized. Under the optimal reaction conditions, the adaptability of eleven alkenone substrates with different structures was investigated. Cu (OTf) 2 as a catalyst precursor and diethyl ether The spatial structure match between the macro-hindered adamantyl and (R) -H_8-binaphthyl groups in ligand (R) -3 was obtained with 98% isolated yield and 72% (R) enantioselectivity The absolute configuration of the product mainly consists of H8-binaphthyl groups in the ligand structure Type decision results demonstrate a new symmetric C_3 monodentate phosphite ligands has potential in asymmetric hydroformylation and 1,4-conjugate addition reaction.