Amido-substituted Malonic Acid Half Oxyesters (MAHOs) have proven to be excellent partners of various aromatic aldehydes in the presence of secondary amine, trifluoromethanesulfonic acid to perform a Knoevenagel–Doebnercondensation under mild conditions with good to excellent yields. A mechanistic study revealed that the sequence involved the formation of an iminium intermediate to provide stereoselectively Z-α,β-unsaturated
Iron-catalysed 1,2-acyl migration of tertiary α-azido ketones and 2-azido-1,3-dicarbonyl compounds
作者:Tonghao Yang、Yajun Lin、Chaoqun Yang、Wei Yu
DOI:10.1039/c9gc02085c
日期:——
Iron-catalysed 1,2-acyl migration of tertiary α-azido ketones and 2-azido-1,3-dicarbonyl compounds provides a simple and atom-economical approach toward enamides and isoquinolones. This paper reports two catalyst systems for these transformations which employ iron(II) complexes [Fe(dpbz)]Br2 (dpbz = 1,2-bis(diphenylphosphino)benzene) and FeBr2/Et3N, respectively. [Fe(dpbz)]Br2 was found to be highly
铁催化的α-叠氮基酮和2-叠氮基-1,3-二羰基化合物的1,2-酰基迁移为酰胺和异喹啉酮提供了一种简单且原子经济的方法。本文报道两种催化剂体系用于这些转化其采用铁(II)配合物的[Fe(dpbz)]溴2(dpbz = 1,2-双(二苯基膦基)苯)和FeBr 2 / ET 3 N,分别。发现[Fe(dpbz)] Br 2在将2-叠氮基-2,3-二氢-1 H-茚满-1-酮转化为异喹诺酮方面非常有效。另一方面,由于Et 3的有益作用,FeBr 2 / Et 3 N的试剂组合具有更宽的催化范围N.后一种催化剂体系可使2-叠氮基-2-甲基-1,3-二羰基化合物在温和条件下以良好的收率转化为相应的酰胺。
BICHEPRu complexes, highly efficient catalysts for asymmetric hydrogenation of carbonyl compounds
[RuX(p-cymene)(bichep)]X, (X = I, Cl) and Ru(OAc)2(bichep) (bichep = 2,2′-bis(dicyclohexylphosphino)-6,6′-dimethyl-1,1′-biphenyl) proved to be highly efficient catalysts for asymmetric hydrogenation of carbonylcompounds bearing phenylglyoxyloyl group under mild conditions.
Optically active complexes of transition metals (RhI, RuII, CoII and NiII) with 2-aminocarbonylpyrrolidine ligands. Selective catalysts for hydrogenation of prochiral olefins
作者:A. Corma、M. Iglesias、C. del Pino、F. Sánchez
DOI:10.1016/0022-328x(92)80121-d
日期:1992.6
The synthesis and characterization of optically active complexes containing organic amides [-C(O)NHR] of the type [RhCl(COD)L], [RhCl(CO)2L], [RhCl(PPh3)2L], [RuCl2(COD)L], [RuCl2(PPh3)2L], [Co(acac)L]X and [Ni(acac)L]X, where L = (S)-2-t-butylaminocarbonylpyrrolidine or (S)-2-(3-triethoxysilyl)propylaminocarbonylpyrrolidine are reported. Their cationic species were prepared in the presence of a non-coordinating
包含[RhCl(COD)L ],[RhCl(CO)2 L ],[RhCl(PPh 3)2 L ],[ RuCl 2(COD)L ],[RuCl 2(PPh 3)2 L ],[Co(acac)L ] X和[Ni(acac)L ] X,其中L =(S)-2-叔丁基氨基羰基吡咯烷或(S报道了)-2-(3-三乙氧基甲硅烷基)丙基氨基羰基吡咯烷。在非配位抗衡离子(X = PF的存在下,制备它们的阳离子物质6 -或C10 4 - )。氨基酸衍生物是双齿的,具有N,N-配位。具有配体的含有三乙氧基甲硅烷基的金属络合物被固定在二氧化硅和改性的USY沸石上。这些配合物已通过光谱和分析技术进行了表征。固定在沸石上的配合物(包含大量的超微孔)显示出更高的烯烃加氢活性,并在乙基氢化中显着提高了对映选择性(> 95%)(Z)-α-苯甲酰基氨基肉桂酸酯为模型,它们代表了均相有机金属催化剂的真正异质对应物。
Synthesis of chiral Rh-bichep complexes, highly efficient catalysts for asymmetric hydrogenations
Chiral cationic and neutral Rh complexes RhX(bichep)(nbd) (XCl,ClO4; nbd=norbornadiene;bichep=2,2′-bis(dicyclohexylphosphino)-6,6′-dimethyl-1,1′-biphenyl) are highly active and excellent catalysts for enantioselective hydrogenation of prochiral olefins and ketones under mild reaction conditions.