Question

11. Which of the following best explains why the synthetic route shown below would be unsuccessful? 2) NaNH2 3) (CHs)hCBr A) The alkynide anion is not a strong enough nucleophile to react with 1-bromopropane in step 1 m amide is not a strong enough base to deprotonate the terminal alkyne in step anion formed by reaction with sodium amide will facilitate an E2 (rather C) The alkynide than SN2) reaction with t-butyl bromide. 5oth substtution reactions will occur on the same end of the alkyne, making a product different than the one shown ) Reaction with sodium amide will result in formation of a primary alkyne. 12. What is the correct order of stability of the following radicals (more stable less a. 1>2 3 b. 2>1 3 c. 2>3> 1 d. 3>2> 1 13. Using correct arrow formalism, draw all the resonance structures for the radical shown below. 14. What term most accurately describes the process shown below? Br+ HBr a) coupling b) proton transfer c) halogen abstraction d) hydrogen abstraction e) homolytic cleavage

Answer 1

CH c) 2 Aadical staliluty C 23 ơnda 13.

Radical Electron Movement 1. Homolytic Cleavage: initiated by light or heat X or hv 2. Addition to a pi bond 3. Hydrogen abstraction: NOT the same as proton transfer 4. Halogen abstraction