Question

explain ir data for 7-Methoxy-1H-indol-6-yl propiolate

IR
(KBr): 3392 (NH), 3259 (C≡CH), 2941, 2810, 2123 (C≡C),
1732 (C═O), (1600, 1500, 1338, 1242, 1200, 1057, 750 cm1)==== specialy

Answer 1

Solution :-

In the IR spectrum the different functional groups shows the peaks at the different frequencies. So using the frequencies of the IR spectrum we can determine the possible groups present in the structure.

Amine hydrogens that is NH - shows the peak at about 3300 to 3600 cm-1 so it shows the peak at 3392 cm-1 for the NH group

C triple bond C-H that is terminal alkyne C-H bond shows the peaks at about the 3259 cm-1

the peaks at the frequency of the 2941 , 2810 and 2123 is the C triple bond C peaks

C triple bond C that is alkyne group shows the specific peak at about 2100 to 2200 cm-1

carbonyl group that is C=O group is spefic group that shows the peak at about 1700 to 1750 cm-1

therefore in the Ir we have 1732 cm-1 peak for the C=O

1600 cm-1 is the peak for the C=C bonds of the ring

1380 cm-1 is the peak for the C-O single bond

peaks below the 1400 cm-1 are the peaks for the C-C and C-H bonds in the alkyl chain.