1999 cyclopropane derivatives

cyclopropane derivativesQ 0021

26 - 084Rh(II)-Catalyzed Asymmetric Cyclopropenation of Propargyl Deriva-tives; Synthesis of Cyclopropene- and cis-Cyclopropaneamino Acids.— The asymmetric cyclopropenation of propargyl halides and amines isinvestigated with a view to the enantioselective synthesis of cyclopropene and-propane analogues of γ-aminobutyric acid. Best results are obtained in cyclo-propenations of propargyl amines doubly protected with electron-withdrawinggroups using Rh2((S)-mepy)4 as catalyst. Absolute configurations of com-pounds (V), (VIIIb), and (XI) are assigned tentatively in analogy to compound(VIIIa) whose configuration is deduced from the optical rotation of (X). —(MUELLER, PAUL; IMOGAI, HASSAN; Tetrahedron: Asymmetry 9 (1998)24, 4419-4428; Dep. Org. Chem., Univ. Geneva, CH-1211 Geneva 4, Switz.; EN)

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