Due before lab begins Answer in space provided For each comp

Due before lab begins. Answer in space provided. For each compound, assign the IR bands which are useful in assigning the molecular structure 1. 4000 3000 1500 1000 SDBS, National Institute of Advanced Industrial Science and Technology 2000 1380 1000 80 SDBS, National Institute of Advanced Industrial Science and Technology

Solution

In the first structure, the importent peak is the stretching vibration of C=O of the ester group. this will come normally in the range above 1700. in the given spectrum also have the peak around 1750. and also the C-O stretching vibration in this ester compound is present around 1150 (normal range is 1050-1300). the alkane C-H stretching frequancy will come just come below 3000 (Range 2800-2950) and the Alkene C-H signal will come just above 3000. and also a weak peak around 1650 is due to the C=C stretching vibration. and also it is cis in nature because in cis conformation, the dipole is slightly strong, so the weak signal can see. if it is transe means the dipole is normal, and the signal will be very veak an can not see properly. so it can confirm that it is cis in nature.

In the second structure, it is a ketone. the C=O stretching normally will come in the range 1680-1780. here also the peak is present around 1730. and also the alkane C-H stretching frequancy will come just come below 3000. these are the important peak to identify the given structure.