Reações e Espectroscopia

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Solutions to Problems . 255 Propagation steps SCH₃ SCH₃ SCH₃ SCH₃ + SCH₃ 57. All cyclopropane-forming reactions. Watch stereochemistry! In all these reactions the original stereochemical relationships around the double bond are preserved. CCl₂ CH₃ (a) H CH₂CH₃ (b) CH₃ H H CBr₂ (c) H H (d) H H CH₃ H CH₂ (e) H (f) from from HC H CH₃ :CH 58. (a), (b) = 6 + 2 1 = 7; degree of unsaturation = (7 5)/2 = 1 π bond or ring. Review Problem 34(b) of Chapter 11 for help, if necessary. The answer is 4.05 5.9 IR assignments: 730 (C-CI); 930 and 980 (terminal alkene); 1630 (C=C); 3090 (alkene C-H). (c) Yes. This is an expected size of coupling for the following structure (see Table 11-2). H H c=c-c- (d) This is a "long-range" (allylic) coupling between the "far" alkene hydrogens and the saturated CH₂ hydrogens: