Yes we can! The vibrational stretching of trans disubstituited alkenes is around 1670 cm-1, that of cis is around 1650 cm-1. Check it out on a good text-book.
[1] Finger print region in IR spectroscopy is also helpful to determine E-Z compounds.
Cis isomer has absorption maxima at slightly shorter wavelength than the trans isomer.
970–960 trans-C-H out-of-plane bend
700 (broad) cis-C-H out-of-plane bend
[2] FTIR allow unambiguous determination of the configuration of the double bonds in long chain unsaturated compounds bearing a RCH=CHR' types of bonds.
Compounds bearing (E,Z) or (Z,E) conjugated moieties show a characteristic "finger print" consisting of 2 bonds as 978-977 and 948-946.
Ok thank you for the answers but my reactant is "imine" derivative so will u plz give me some more info so that i get a clear solution!!!!!!!
DO you mean that you would like to know the E/Z configuration of an imine?
If your compound is an imine, then you've got both stereoisomers - (E)- and (Z)- imines cannot be separated.
You can, however, determine the (E):(Z) ratio in the mixture by NMR (NOESY experiment is imo the easiest route to differentiate between the isomers).
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