Iron‐catalyzed Cross‐Coupling of Propargyl Carboxylates and Grignard Reagents: Synthesis of Substituted Allenes
نویسندگان
چکیده
Presented herein is a mild, facile, and efficient iron-catalyzed synthesis of substituted allenes from propargyl carboxylates and Grignard reagents. Only 1-5 mol % of the inexpensive and environmentally benign [Fe(acac)3 ] at -20 °C was sufficient to afford a broad range of substituted allenes in excellent yields. The method tolerates a variety of functional groups.
منابع مشابه
A Synthesis of Substituted α-Allenols via Iron-Catalyzed Cross-Coupling of Propargyl Carboxylates with Grignard Reagents
α-Allenols are attractive and versatile compounds whose preparation can be a nontrivial task. In this Letter, we provide a method for the prompt synthesis of substituted α-allenols via a catalytic cross-coupling reaction which makes use of a nontoxic and cost-effective iron catalyst. The catalyst loading is typically as low as 1-5 mol %. The mild reaction conditions (-20 °C) and the short react...
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