[EN] SYNTHESIS OF PELORUSIDE A AND ANALOGS THEREOF FOR USE AS ANTITUMOR AGENTS [FR] SYNTHESE DU PELORUSIDE A ET ANALOGUES DE CELUI-CI POUVANT ETRE UTILISES EN TANT QU'AGENTS ANTITUMORAUX
An improved synthesis of Kagan’s menthyl substituted titanocene and zirconocene dichloride, comparison of their crystal structures, and preliminary catalyst evaluation
An improved synthesis of 1 and 2 is described that allows access to these complexes in multigram quantities necessary for catalytic applications. The crystal structures of 1 and 2 are compared and the conformational preferences of the ligands, that are important for catalytic applications, are discussed. Complex 2 was evaluated as a catalyst for carbomagnesation reactions.
terminal alkenes catalysed by (R,R)-ethylene-1,2-bis(η5-4,5,6,7-tetrahydro-1-indenyl)zirconium(R)-1,1′-binaphth-2,2′-diolate gave low turnovers and enantioexcesses. A novel Ci symmetric zirconocene dichloride CpCp′ZrCl2 (Cp = C5H5, Cp′ = 1-neomenthyl-4,5,6,7-tetrahydroindenyl) was prepared which gave better enantioselectivity, is cheaper to make, catalytically more active, and recoverable.
通过催化末端烯烃的ethylmagnesiation([R ,- [R )-亚乙基-1,2-双(η 5 -4,5,6,7-四氢-1-茚基)合锆([R)-1,1'- binaphth- 2,2'-羟乙酸盐产生较低的营业额和对映体过量。制备了一种新的C i对称的二茂锆锆CpCp'ZrCl 2(Cp = C 5 H 5,Cp'= 1-新薄荷基-4,5,6,7-四氢茚基),该对映体具有更好的对映选择性,制造成本更低,催化作用更多。活跃且可恢复。
Zirconium-catalyzed asymmetric carbomagnesation
作者:James P. Morken、Mary T. Didiuk、Amir H. Hoveyda
DOI:10.1021/ja00068a077
日期:1993.7
Zirconium-catalysed enantioselective 2-aluminoethylalumination of alkenes
作者:Graham Dawson、Charles A. Durrant、George G. Kirk、Richard J. Whitby、Raymond V.H. Jones、Michael C.H. Standen
DOI:10.1016/s0040-4039(97)00308-0
日期:1997.3
Asymmetric 2-aluminoethylalumination of mono-substituted alkenes and 2,5-dihydrofurans catalysed by (R,R)-ethylene-1,2-bis(eta(5)-4,5,6,7-tetrahydro-1-indenyl)zirconium (R)-1,1'-binaphth-2,2'-diolate 4 and eta(5)-cyclopentadienyl-eta(5)-(1-neomenthyl-4,5,6,7-tetrahydroindenyl)zirconium dichloride 5. gave 30 - 99% enantiomeric excesses. The so formed organoaluminium has potential for further elaboration leading to enantiomerically enriched products. (C) 1997 Elsevier Science Ltd.
Total Synthesis and Absolute Configuration of the Novel Microtubule-Stabilizing Agent Peloruside A