Development of catalytic asymmetric reactions based on design and synthesis of original chiral ligands

合理设计和合成新型手性配体催化不对称反应是当前有机合成化学研究的热点。我们合成了一些新的手性化合物，包括螺二茚满双亚磷酸酯、双恶唑啉和N-氧化物，它们作为手性配体在几个不对称反应中得到了应用。主要研究结果如下：（1）利用手性铑（II）配合物催化的双重氮化合物分子内C-H双插入反应，实现了一锅法高效合成光学活性1，1 '-螺二茚满-3，3'-二酮衍生物。螺二茚二酮很容易被转化为螺二茚二亚磷酸酯，这被发现是一个有效的手性配体钯催化烯丙基烷基化和铑催化Pauson-Khand反应。(2)通过铑催化的不对称C-H插入反应合成的新型双恶唑啉配体已被证明是铜催化的Diels-Alder反应和环丙烷化反应的有效手性配体。(3)利用手性铑（H）配合物，实现了重氮酯中烯丙基氧鎓或锍叶立德的串联分子内生成和重排。(4)一种新的手性联吡啶N，N ′-二氧化物镉配合物催化硫醇对映选择性共轭加成生成硫化物的方法。(5)以手性N，N '-二氧化钪配合物为催化剂，β-酮酸酯与甲基乙烯基酮的Michael加成反应具有良好的对映选择性。(6)手性N，N '-二氧化物催化四氯化硅对映选择性开环生成光学活性氯代醇。

The rational design and synthesis of novel chiral ligands directed toward catalytic asymmetric reactionsis currently the focus of attention in synthetic organic chemistry. We have synthesized novel chiral compounds including spirobiindanbisphosphites, bisoxazolines, and N-oxides, which were utilized in several enantioselective reactions as chiral ligands. The results we have obtained are as follows; (1) A highly efficient one-pot construction of optically active 1,1'-spirobiindan-3,3'-dione derivatives has been achieved by exploiting double intramolecular C-H insertion reaction of bisdiazo compounds catalyzed by chiral rhodium(II) complex. The spirobiindandione was easily converted to spirobiindanbisphosphite, which was found to be an efficient chiral ligand for palladium-catalyzed allylic alkylation and rhodium-catalyzed Pauson-Khand reaction. (2) Novel bisoxazoline ligands prepared via rhodium-catalyzed enantioselective C-H insertion reaction have proven to be an efficient chiral ligand for copper-catalyzed Diels-Alder reaction and cyclopropanation. (3) Tandem intramolecular generation and rearrangement of allylic oxomium or sulfonium ylides from diazoesters has been effected with the aid of chiral rhodium(H) complex. (4) A novel method of enantioselective conjugate additions of thiols produced sulfides employing a cadmium complexes of chiral bipyridine N,N'-dioxide as a catalyst. (5) An enantioselective Michael addition of β-keto esters to methyl vinyl ketone employing a chiral N,N'-dioxide-scandium complex as a catalyst afforded the a Michael adduct with good enantioselectivity. (6) Chiral N,N'-dioxides catalyzed enantioselective ring opening of meso-epoxides with silicon tetrachloride to produce optically active chlorohydrins.