Polylithiumorganic compounds—23. 3, 4-Dilithio-1, 2-butadienes by addition of lithium metal to 1, 4-unsymmetrically substituted butatrienes

A Maercker, H Wunderlich, U Girreser

Index: Maercker, Adalbert; Wunderlich, Hans; Girreser, Ulrich Tetrahedron, 1996 , vol. 52, # 17 p. 6149 - 6172

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Citation Number: 15

Abstract

The synthesis of the highly reactive 1, 4-unsymmetrically substituted butatrienes 12a-c is described. When employing a strict synthetic protocol, these alkatrienes react with lithium metal to 3, 4-dilithio-1, 2-butadienes 20a-c as stable intermediates. The structure of 20 is supported by IR and NMR spectroscopic evidence. The same dianionic intermediate can be prepared in one case by double deprotonation of the 1, 2-butadiene 19. Upon ...