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198 Chapter 10 USING NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY TO DEDUCE STRUCTURE (a) 2 signals: (b) 2 signals: 0.9 1.3 1.5 3.8 (c) 3 signals: (d) 4 signals: Variable 4.0 1.4 0.9 1.5 1.3 0.9 (e) 2 signals: (CH₃)₃C-NH₂ (f) 3 signals: (CH₃CH₂)₃CH 1.3 Variable 0.9 1.3 1.5 (g) 4 signals: 3.4 3.8 1.7 1.0 (h) 2 signals: CH₂ CH 2 CH₂ 1.5 2.4 O (i) 3 signals: CH₃-CH₂-C H 9.5 1.2 2.0 3.4 CH3O CH₃ (j) 4 signals: CH₃ 1.4 4.0 37. As in the previous problem, the chemical shifts are approximations. Chemical boxes are most useful for distinguishing structures. Integrations are given in parentheses. Signals marked with asterisks (*) will be complicated as a result of the presence of a chiral carbon in the molecule (see Chemical Highlight 10-3 for further details). CH₃ 1.1 (3) (a) 1.5 1.8 1.1 3.5 2.0 1.5 0.9 (6) (2) (3) (2)* (1) (2)* (3) 0.9 1.6 1.8 3.5 (6) (1) (2) (2)