【作者】 樊保敏；

【导师】 周其林； 涂永强；

【作者基本信息】 兰州大学 ， 有机化学， 2006， 博士

【摘要】 五元或六元环状结构普遍存在于天然产物和生物活性分子中,而过渡金属催化的1,6-烯炔类底物的环化反应则是构筑五元或六元环状结构非常有效的合成方法。近年来,随着研究的深入,已经实现了1,6-烯炔类底物多种形式的不对称催化环化反应。但是,这些催化反应大多面临着手性配体类型单一、底物适用范围窄、反应结果仍需要进一步提高等许多问题。因此引入新的手性配体,发展更加高效的手性催化剂来实现1,6-烯炔类底物的不对称环化反应仍然是化学家们面临的挑战。于是,我们欲将手性螺环磷配体应用到该类反应中,研究其在铑催化1,6-烯炔不对称环化反应中的催化活性和手性诱导性能,以期开发高效的手性催化剂。 在研究铑催化的1,6-烯炔不对称Pauson-Khand反应时,我们发现手性螺环双膦配体SDP的铑络合物是该反应非常有效的催化剂。在优化的反应条件下,一系列1,6-烯炔底物被高收率地转化为相应的双环环戊烯酮化合物,同时获得较好的对映选择性,ee值最高达到86%。 随后,我们尝试将手性螺环单磷配体如SIPHOS应用到1,6-烯炔的不对称Pauson-Khand反应中。在SIPHOS-Rh（Ⅰ）催化剂的作用下,同样得到了较好的结果。所得双环环戊烯酮产物的ee值可达84%,反应收率也28-73%之间。这是第一例采用手性单磷配体获得高对映选择性的不对称Puason-Khand反应。 在此研究基础上,我们进一步研究了1,6-烯炔的不对称硅氢化环化反应。研究结果表明,螺环手性双膦配体SDP和[Rh（COD）₂]BF₄的络合物是目前该反应中最高效的手性催化剂。在DCE作溶剂的条件下,一系列1,6-烯炔都可以被该催化剂转化为相应的硅氢化环化产物,产物的ee值大多数在90%以上,最高可以达到99.5%。这是目前该反应所取得的最好结果。 此外,我们还研究了螺环手性单磷配体在铑催化的芳基乙烯底物不对称氢甲酰化反应中的应用。发现SIPHOS-ⁱPr配体的效果最好,它的铑络合物用于该反应得到非常好的收率（最高达99%）和区域选择性（最高达97%）,但对映选择性仍然较低,ee值最高达到44%。更多还原

【Abstract】 The transition metal-catalyzed carbocyclizations of 1,6-enynes are efficient and atom-economic methods to construct 5- or 6-membered ring frameworks, which widely exist in nature products and biologically active molecules. Recently, the asymmetric versions of some of these carbocyclizations have been achieved. However, the catalysts used in these asymmetric reactions are mainly limited to the metal complexes contained chiral atropoisomeric diphosphine ligands such as BINAP and BIPHEMP, and the enantioselectivities and substrate scopes of many of these reactions are far from beening satisfied. Thus, the development of efficient ligands catalysts for asymmetric carbocyclizations of 1,6-enynes remain to be a challenge for organic chemists. In this thesis we investigated the application of the chiral spiro phosphorus ligands in the rhodium catalyzed asymmetric carbocyclizations of 1,6-enynes.In the study of Rh（I）-catalyzed asymmetric Pauson-Khand reaction, we found that chiral spiro diphosphine ligand SDP was efficient. Under the optimized reaction conditions, the Rh（I）-SDP complex could convert a variety of 1,6-enynes to bicyclopentenone derivatives under CO atmosphere in high yields with good enantioselectivities. The ee values were up to 86% ee, which were comparable with those obtained by using BINAP type ligands.The monodentated chiral spiro ligands SIPHOS were also efficient for Rh-catalyzed Pauson-Khand reaction. By using SIPHOS-Rh（I） complex as catalyst, the cyclization products were produced in good yields and up to 84 % ee of enantioselectivities. This was the first example using monodentated phosphorus ligands to achieve a high enantioselectivity in the Rh（I）-catalyzed asymmetric Pauson-Khand reaction.In the Rh（I）-catalyzed asymmetric hydrosilylation/cyclization reaction of 1,6-enynes, chiral spiro diphosphine SDP ligands were demonstrated to be highly enantioselective. When the in situ generated catalyst from SDP and [Rh（COD）₂]BF₄ was used, a series of 1,6-enynes could react with silanes to provide the silylalkylidene cyclopentane or pyrrolidine derivatives in good yields with excellent enantioselectivties （up to 99.5% ee）.This is the best result obtained in this reaction to date.Moreover, we had studied the Rh（I）-catalyzed asymmetric hydroformylation of vinyl arenes using monophosphorous Iigands. The spiro monophosphoramidite SIPHOS- ’Pr was the best ligand, providing the hydroformylation products in excellent yields （up to 99 %） with high regioselectivities （up to 97 %）, and moderate enantioselectivities （up to 44 % ee）.更多还原