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Striking reactivity of ylide-like germylene toward terminal alkynes: [4+2] cycloaddition versus C-H bond activation

Shenglai Yao1, Christoph van Wüllen, Matthias Driess

  • 1Technische Universität Berlin, Institute of Chemistry: Metalorganics and Inorganic Materials, Sekr. C2, Strasse des 17. Juni 135, Berlin, Germany.

Chemical Communications (Cambridge, England)
|November 6, 2008
PubMed

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Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
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