Spirocyclic compounds, such as compound 3, are made and used by insects for the purposes of communication. The first step of a synthesis of compound 3 involves treatment of (S)-1,2-epoxypropane (compound 1) with lithium acetylide, followed by acid workup, to give compound 2, as shown below (J. Org. Chem. 2005, 70, 3054-3065). Identify the structure of compound 2 and provide a mechanism for its formation. (Hint: The carbon-lithium bond reacts in a way that is similar to the carbon-magnesium bond of a Grignard reagent.) 1 1) Li—= 2) H3O+ C5H8O 2 3

Spirocyclic compounds, such as compound 3, are made and used by insects for the purposes of communication. The first step of a synthesis of compound 3 involves treatment of (S)-1,2-epoxypropane (compound 1) with lithium acetylide, followed by acid workup, to give compound 2, as shown below (J. Org. Chem. 2005, 70, 3054-3065). Identify the structure of compound 2 and provide a mechanism for its formation. (Hint: The carbon-lithium bond reacts in a way that is similar to the carbon-magnesium bond of a Grignard reagent.) 1 1) Li—= 2) H3O+ C5H8O 2 3

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

Chapter21: Benzene And The Concept Of Aromaticity

Section: Chapter Questions

Problem 21.55P

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