Disiamylborane adds only once to alkynes by virtue of its two bulky secondary isoamylgroups. Disiamylborane is prepared by the reaction of BH3 # THF with an alkene.(a) Draw the structural formulas of the reagents and the products in the preparation ofdisiamylborane.(b) Explain why the reaction in part (a) goes only as far as the dialkylborane. Why isSia3B not formed?

Disiamylborane adds only once to alkynes by virtue of its two bulky secondary isoamylgroups. Disiamylborane is prepared by the reaction of BH3 # THF with an alkene.(a) Draw the structural formulas of the reagents and the products in the preparation ofdisiamylborane.(b) Explain why the reaction in part (a) goes only as far as the dialkylborane. Why isSia3B not formed?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter7: Alkynes

Section: Chapter Questions

Problem 7.26P

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