Proton NMR Chemical Shifts

Flashcards for learning and reviewing different types of protons and their characteristic chemical shift values in proton NMR spectroscopy.

Methyl Proton ($R\text{-CH}_3$)

($\delta$) of approximately $0.9$.

Methylene Proton ($\text{-CH}_2\text{-}$)

A type of proton characterized by a chemical shift ($\delta$) of approximately $1.2$.

Methine Proton

A type of proton attached to a tertiary carbon ($\text{>CH-}$), characterized by a chemical shift ($\delta$) of approximately $1.7$.

Allylic Proton

A proton attached to a carbon adjacent to a carbon-carbon double bond, characterized by a chemical shift ($\delta$) of approximately $2$.

Alkynyl Proton ($R\text{-C}\equiv\text{C-H}$)

A proton attached to a carbon-carbon triple bond, characterized by a chemical shift ($\delta$) of approximately $2.5$.

Benzylic Methyl Proton

A methyl group proton directly attached to an aromatic ring ($\text{Ar-CH}_3$), characterized by a chemical shift ($\delta$) of approximately $2.5$.

Alkyl Halide Proton

A proton on a carbon bonded to a halogen ($\text{R}_2\text{C(H)-X}$), with a chemical shift ($\delta$) ranging from $2$ to $4$.

Alcohol Proton ($R\text{-O-H}$)

A hydroxyl proton in an alcohol, characterized by a chemical shift ($\delta$) ranging from $2$ to $5$.

Vinylic Proton

A proton directly attached to a carbon-carbon double bond, characterized by a chemical shift ($\delta$) ranging from $4.5$ to $6.5$.

Aryl Proton

A proton directly attached to an aromatic ring, characterized by a chemical shift ($\delta$) ranging from $6.5$ to $8$.

Aldehyde Proton

A proton directly attached to a carbonyl carbon ($\text{R-C(=O)H}$), characterized by a chemical shift ($\delta$) of approximately $10$.

Carboxylic Acid Proton

A proton belonging to the hydroxyl group of a carboxylic acid ($\text{R-C(=O)OH}$), characterized by a chemical shift ($\delta$) of approximately $12$.

Proton NMR Chemical Shift Reference Table

A reference table providing the typical chemical shift ($\delta$) values in ppm for various structural types of protons.