A strictly "pair"-selective synthesis of conjugated diynes via Pd-catalyzed cross coupling of 1,3-diynylzincs: A superior alternative to the Cadiot-Chodkiewicz reaction
E. Negishi et al., A strictly "pair"-selective synthesis of conjugated diynes via Pd-catalyzed cross coupling of 1,3-diynylzincs: A superior alternative to the Cadiot-Chodkiewicz reaction, ORG LETT, 2(23), 2000, pp. 3687-3689
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A strictly "pair"-selective synthesis of conjugated diynes via Pd-catalyzed
cross coupling of 1,3-diynylzincs is described. This method, like the Cadi
ot-Chodkiewicz reaction, requires three steps for the synthesis of (RC)-C-1
=CC=CR2 from (RC)-C-1=CH, (RX)-X-2, and HC=CH. However, the high "pair"-sel
ectivity permitting high yield production of the desired conjugated diynes
without separation of symmetrical diynes promises to make the present proto
col superior to the Cadiot-Chodkiewicz reaction in many cases.