Assign the ¹H NMR spectra for the phosphonium salt (Ph3P+CH₂CO₂Et Br), ylid (Ph3P=CHCO2Et) and product A (i.e. decide which H environment corresponds to each signal). [Note the two-bond coupling of the a-hydrogen to phosphorus (H-C-P) is observed because P has a nuclear spin of 12]. ¹H NMR data for the phosphonium salt Ph3P+CH₂CO₂Et Br Chemical Shift (ō) 7.98-7.78 7.75-7.65 5.45 4.02 1.05-1.15 Integration (in mm) Br Integral (Number of H's) Splitting Pattern (s, d, t, m.., etc) Assignment

Assign the ¹H NMR spectra for the phosphonium salt (Ph3P+CH₂CO₂Et Br), ylid (Ph3P=CHCO2Et) and product A (i.e. decide which H environment corresponds to each signal). [Note the two-bond coupling of the a-hydrogen to phosphorus (H-C-P) is observed because P has a nuclear spin of 12]. ¹H NMR data for the phosphonium salt Ph3P+CH₂CO₂Et Br Chemical Shift (ō) 7.98-7.78 7.75-7.65 5.45 4.02 1.05-1.15 Integration (in mm) Br Integral (Number of H's) Splitting Pattern (s, d, t, m.., etc) Assignment

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter19: Nuclear Magnetic Resonance Spectroscopy

Section: Chapter Questions

Problem 19.3QAP

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