What is the pKa of a ketone?

The alpha-hydrogens of ketones (pKa = 20) are less acidic as compared to aldehydes (pKa = 17). This is because the alkyl group R” of ketones pushes electrons via inductive effect on to the alpha-carbon.

What does the pKa of a functional group tell you?

Predicting the more acidic compound If both molecules contain one functional group, then you simply need to look up the pKa values. The one with a lower pKa value is more acidic. For example, which of the following two molecules is more acidic? The pKa of carboxylic acids is ~5 and the pKa of phenol is ~10.

What is the pKa of carboxylic acid?

~ 5
The pKa of carboxylic acids typically ~ 5. They are significantly more acidic than water or alcohols.

Is pyridine a functional group?

In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule’s characteristic chemical reactions….Groups containing nitrogen.

What is the pKa of imine?

approximately 7
Recall from section 7.5B that imines have a pKa of approximately 7, so at physiological pH they can be accurately drawn as either protonated (iminium ion form) or neutral (imine).

What does pKa tell us about amino acids?

The pKa value given for the amino group on any amino acid specifically refers to the equilibrium between the protonated positive nitrogen and deprotonated neutral nitrogen. You’ll never see a neutral nitrogen deprotonated to form a negative on an amino acid.

What is the pKa of hno3?

p-Toluenesulfonic acid: pKa = -2.8. Nitric acid (HNO3): pKa ≈ -1.4. Chloric acid (HClO3): pKa ≈ 1.0.

Are ketones acidic?

Ketones are acidic molecules, so an increased level of ketones can cause the blood to become more acidic which prevents the body’s processes from working normally. By definition, ketone levels in DKA are too high, causing the blood to become dangerously acidic.

What is the functional group of ketone?

Aldehydes and ketones are organic compounds which incorporate a carbonyl functional group, C=O. The carbon atom of this group has two remaining bonds that may be occupied by hydrogen or alkyl or aryl substituents.

What are the values of PKA in organic chemistry?

Carboxylic acids 4, 8 Pyrazine 26 Aliphatic 4, 8 Aromatic 7, 8 Quinoline 27 Phenols 9 Quinazoline 27 Alcohols and oxygen acids 10, 11 Quinoxaline 27 Amino Acids 12 Special Nitrogen Compounds 28 Peptides 13 Hydroxylamines 28 Nitrogen Compounds 14 Hydrazines 28 Aliphatic amines 15, 17, 19 Semicarbazones 28 Cyanoamines 16 Amidoximes 28

What is the alpha proton of amide pKa?

Alcohol   pKa = 16‐18. 8. Water  pKa = 15.7. 9. Amide   pKa = 18. 10. Alpha proton of ketone/aldehyde  pKa = 20. 11.   Alpha proton of ester   pKa = 25.

What is the pKa value of phenazine?

pKa Data Compiled by R. Williams pKa Values INDEX Inorganic 2 Phenazine 24 Phosphates 3 Pyridine 25 Carboxylic acids 4, 8 Pyrazine 26 Aliphatic 4, 8

Which is an example of a pKa group?

Alkene:  vinyl 45‐50; allylic 43 16. Alkane  pKa = above 50  Examples: H H H H H (vinyl) (allylic) (aryl) (benzylic) N H H O H O OH NH2 O SH CH3 O OH H2 N OH OH O H O OH2