Editing Alkene (section)

=== NMR spectroscopy ===
In <sup>1</sup>H [[NMR]] spectroscopy, the [[hydrogen]] bonded to the carbon adjacent to double bonds will give a [[chemical shift|δ<sub>H</sub>]] of 4.5–6.5&nbsp;[[parts per million|ppm]]. The double bond will also [[Electromagnetic shielding|deshield]] the hydrogen attached to the carbons adjacent to sp<sup>2</sup> carbons, and this generates δ<sub>H</sub>=1.6–2.&nbsp;ppm peaks.<ref>{{cite web|url=http://www2.ups.edu/faculty/hanson/Spectroscopy/NMR/HNMRshift.htm|title=Overview of Chemical Shifts in H-NMR|last=Hanson|first=John|website=ups.edu|access-date=May 5, 2019}}</ref> Cis/trans isomers are distinguishable due to different [[J-coupling]] effect. Cis [[Vicinal (chemistry)|vicinal]] hydrogens will have coupling constants in the range of 6–14&nbsp;[[Hz]], whereas the trans will have coupling constants of 11–18&nbsp;Hz.<ref name="NMR of Alkenes">{{cite web|url=https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Alkenes/Properties_of_Alkenes/Nuclear_Magnetic_Resonance_(NMR)_of_Alkenes|author=<!--Not stated-->|title=Nuclear Magnetic Resonance (NMR) of Alkenes|website=Chemistry LibreTexts|date=April 23, 2019|access-date=May 5, 2019}}</ref>

In their <sup>13</sup>C NMR spectra of alkenes, double bonds also deshield the carbons, making them have low field shift. C=C double bonds usually have chemical shift of about 100–170&nbsp;ppm.<ref name="NMR of Alkenes" />