13C NMR (intro)
NMR Spectroscopy · Chemistry
Study notes
How many ¹³C signals for 2-butanone (CH₃COCH₂CH₃)? Step 1: Proton-decoupled → one signal per unique carbon. Step 2: Carbons: CH₃(C=O)–C(=O)–CH₂–CH₃ — all four distinct. Step 3: Expect 4 signals: ~210 (C=O), ~35 (CH₂), ~25, ~8 (CH₃s). Step 4: Four signals — symmetry (or not) counted in carbons!