I was asked an interesting question by an Organic Chemistry faculty member. In a chiral molecule an ethyl group, CH3-CH2, can have two different chemical shifts for the two geminal protons on the CH2 group. But I've never seen a double-doublet for the methyl group, always a triplet. Why can't the two vicinal J values be different if the two protons on the CH2 are not equivalent?
Answers that could be understood by an Organic chemist (including myself in that category) would be much appreciated.
Neil
Neil E. Jacobsen, Ph.D.
NMR Facility Manager
Department of Chemistry and Biochemistry
University of Arizona
1306 E University Blvd.
Tucson, AZ 85721
520-621-8146
Received on Wed Nov 26 2014 - 10:49:39 MST