【作者】 何可；

【导师】 唐除痴；

【作者基本信息】 南开大学 ， 有机化学， 2004， 博士

【摘要】 在醛的不对称硅氰化反应中,从D-樟脑出发,设计并合成了一类新的具有游离酚羟基的手性环状膦酰二胺(+)-c 和(+)-d。通过重结晶的方法培养了三个手性环状膦(磷)酰二胺的单晶,对它们进行了X 光衍射晶体结构分析,并确定了它们的绝对构型。考察了此类手性磷试剂作为配体催化剂在醛的不对称硅氰化反应中的催化效果。对反应条件如催化剂用量、反应温度、反应底物及催化剂结构等进行了优化选择。结果表明,此类手性磷化合物有较好的催化活性。以(+)-d 为配体催化剂,邻甲氧基苯甲醛为反应底物,得到98.3%的对映选择性。在合成(+)-c 和(+)-d 的过程中,研究了正丁基锂作用下磷酰基从氧到碳的重排反应,确定该重排反应的动态立体化学对磷原子来说是构型保留,并深入讨论了该重排反应的机理。在不对称Baylis-Hillman 反应中,从多种便宜易得的手性源出发合成了5 类手性活化烯。在Me3N·H2O/溶剂体系中,研究了它们的不对称Baylis-Hillman 反应,取得了较好的不对称诱导效果。其中,丙烯酸薄荷醇酯与醛的反应,de 值最高可达98.4%;N-α-苯乙基丙烯酸酰胺与醛的反应,非对映选择性高达97.4%。将Salen 钴(Ⅱ)配体与叔胺作为催化剂共同催化Baylis-Hillman 反应,得到具有一定旋光值的产物。更多还原

【Abstract】 In the research of asymmetric silylcyanation, a novel class of chiral cyclophosphonodiamides (+)-c and (+)-d containing a free phenolic hydroxyl group were designed and synthesized starting from D-camphor. Three crystals of the optically active cyclic phosphorodiamidates and phosphonodiamide were prepared by recrystallization. The absolute configurations of these compounds were determined via X-ray diffraction analyses. The catalytic activity of the chiral phosphorus compounds in the asymmetric silylcyanation of aromatic aldehydes was investigated. The influence of different factors, such as amount of catalyst, reaction temperature, substrate and structure of catalyst, on the enantioselectivity of the reaction was also discussed. It was found that this type of chiral phosphorus reagent has good catalytic activity for the asymmetric silylcyanation reaction. When o-methoxybenzaldehyde was used as substrate, excellent enantioselectivity (98.3%) was observed in the presence of (+)-d as ligand catalyst. The P-O to P-C rearrangement upon treatment of cyclophosphorodiamidates with n-BuLi was studied. Crystallographic study revealed that this rearrangement reaction proceeded with total retention of configuration at the phosphorus atom. For the asymmetric Baylis-Hillman reaction, five chiral activated alkened were synthesized starting form readily available chiral sources and their asymmetric induction ability in the asymmetric Baylis-Hillman reaction were examined. In Me3N.H2O/solvent system, (-)-menthyl acrylate and N-α-phenylethyl acrylamide were found to be highly effective to the diastereoselective Baylis-Hillman reaction. The corresponding chiral adducts were obtained with high diastereomeric excesses (up to 98.4% and 97.4% de, respectively). Enantiomerically enriched adducts were formed in the asymmetric Bayli-Hillman reaction employing (salen)Co(II) combined with tertiary amines as catalysts.更多还原