CAJ | 학술논문

以恶唑啉为导向基团,通过邻位锂化方便地高非对映选择性地合成了一系列平面手性二茂铁硫恶唑啉、硒恶唑啉和膦恶唑啉配体.应用于1,3-二苯基烯丙基醋酸酯的烯丙基烷基化反应,ee值最高可达99%,膦氮配体在烯丙基胺化反应中,ee值最高也可达97%.此外,发现中心手性起到了决定产物ee值和绝对构型的作用,平面手性和中心手性的匹配在取得高对映选择性上是重要的.设计合成的一类平面手性二茂铁修饰的手性口袋型双膦配体,由于有平面手性的辅助而具有更有效的诱导效应.这类配体在前手性亲核试剂的不对称烯丙基化生成季碳氨基酸衍生物构及alpha-位双取代季碳酮反应中,ee值最高分别可达到75%和95%.设计合成的1,1-二茂铁膦氮配体,在单取代的烯丙基醋酸酯的钯催化区域选择性及对映选择性的烯丙基烷基化及胺化反应中,显示了非常高的反应活性、区域选择性和对映选择性.配体中BINOL羟基由于和苄胺存在分子间氢键而对反应的选择性起到了关键作用,并从实验上给予了证明.
이악서람위도향기단,통과린위리화방편지고비대영선택성지합성료일계렬평면수성이무철류악서람、서악서람화련악서람배체.응용우1,3-이분기희병기작산지적희병기완기화반응,ee치최고가체99%,련담배체재희병기알화반응중,ee치최고야가체97%.차외,발현중심수성기도료결정산물ee치화절대구형적작용,평면수성화중심수성적필배재취득고대영선택성상시중요적.설계합성적일류평면수성이무철수식적수성구대형쌍련배체,유우유평면수성적보조이구유경유효적유도효응.저류배체재전수성친핵시제적불대칭희병기화생성계탄안기산연생물구급alpha-위쌍취대계탄동반응중,ee치최고분별가체도75%화95%.설계합성적1,1-이무철련담배체,재단취대적희병기작산지적파최화구역선택성급대영선택성적희병기완기화급알화반응중,현시료비상고적반응활성、구역선택성화대영선택성.배체중BINOL간기유우화변알존재분자간경건이대반응적선택성기도료관건작용,병종실험상급여료증명.
Thioether, selenide and phosphino-derivatives of ferrocenyl oxazolines, synthesized from ferrocenyl oxazolines, were found to be effective in palladium-catalyzed allylic alkylation with up to 99% ee. With P, N-ligand, palladium-catalyzed allylic amination was achieved with 97% ee. The enantio-control was dominated by the central chirality. However,the match between planar chirality and central chirality is critical for high enantioselectivity.A series of planar chiral ferrocene modified bisphosphine pocket ligands were synthesized and found to be very effective in construction of quaternary carbon centers using asymmetric allylic alkylation. Some non-coded alpha, alpha-disubstituted amino acids were obtained with up to 75% ee using ketone imino esters. Using enolate of simple ketone as nucleophile, alpha, alpha-disubstituted ketones were obtained with up to 95% ee. A new type of ferrocene based P, N-ligands has been synthesized and was found to be very effective in regio- and enantio-selective palladium-catalyzed allylic alkylation and amination of mono-substituted allylic acetates. The free OH in the ligand was very important for selective control by the hydrogen bonding with benzylamine in later reaction, which was proved by experimental results.