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Solutions to Problems 139 (c) Not at all. No appreciable reaction besides with the solvent. (d) Well. An "intramolecular" (internal) reaction. (e) Well, eventually, but very, very slowly. (f) Well. (g) Well. (h) Not at all. No reaction because of the very poor nucleophile. (i) Not at all. No reaction. (j) Not at all. No reaction because of the very poor leaving group. (k) Poorly. forms also. Poorly. Good nucleophile gives mainly Br₂, KI, DMSO 50. (a) CH₃CH₂CH₂CH₃ CH₃CH₂CHBrCH₃ CH₃CH₂CHICH₃ Cl₂, hv Nal, acetone (b) CH₃CH₂CH₂CH₃ some CH₃CH₂CH₂CH₂I hv KOH, H₂O Br₂, (c) CH₄ CH₃Cl CH₃OH; then (CH₃)₃CH (CH₃)₃CBr (CH₃)₃COCH₃ Br Br₂, hv KOCH₂CH₃, CH₃CH₂OH (d) Br OH H₂O (SN1) (e) From (d), A better method will be presented in Chapter 8. (f) Na₂S in alcohol: Br Br CH₂ CH₂ CH₂ CH₂ Four SN2 displacements! CH₂ S²⁻ CH₂ Br Br 51. (a) Rate = k[RBr], so 2 X 10⁻⁴ = k(0.1), and therefore k = 2 X 10⁻³ s⁻¹. Product is OH (ROH). (b) New = 4 X s⁻¹. Addition of LiCl increases the polarity of the solution by adding ions, and this speeds up the rate-determining ionization step in the solvolysis process.