Question

If the melting point ranges of your dimethone and dimethone anhydride derivatives were the same, what common analytical techniques (not including NMR or mass spectrometry) could you use to establish if the compounds were the same or different? List at least two techniques and state how they could be used to answer the question.

Answer 1

Ans) Though their melting points are similar, the following analytical methods to discriminate the two compounds as follows

a) Infrared spectroscopy:Dimethone derivatives show peak for -OH group with high intensity at 3200-3650cm-1 but in case of Dimehone anhydride derivative, like ether, shows peak at -C-O-C- between 1070 and 1150cm-1

b) Thin layer chromatography: In this method their Rf values are calculated and compare with standard substacnes. So the above substance show different values of Rf.