The greatly increased boiling point is due to the fact that butanol contains a hydroxyl group, which is capable of hydrogen bonding.

Amines have lower boiling points than alcohols because nitrogen is less electronegative than oxygen. As a result the N—H bond is less polar than the O—H bond, and the hydrogen bond in amines is weaker than the hydrogen bond in alcohols.

1-Aminobutane is a 1∘-amine has the highest boiling point du to more association by H-bonding.

Primary amines- In primary amines, only one of the hydrogen atoms in the ammonia molecule has been replaced. Mostly in primary amines two hydrogens are present that form a stronger hydrogen bond as compared to tertiary amines hence it has a higher boiling point.

It is useful to compare the boiling point of methylamine, CH3NH2, with that of ethane, CH3CH3. The reason for the higher boiling points of the primary amines is that they can form hydrogen bonds with each other as well as van der Waals dispersion forces and dipole-dipole interactions.

Most amides are solids at room temperature; the boiling points of amides are much higher than those of alcohols of similar molar mass.

Amides have the highest boiling points of all acid derivatives. This is not only due to the dipole-dipole interaction; hydrogen bonding is also experienced by main and secondary amides. Tertiary amides lack N-H bonds and are unable to engage in hydrogen bonding, but are strong acceptors of hydrogen bonds.

Primary and secondary amides can have hydrogen bonding, and therefore have high boiling points and melting points. Tertiary amides cannot hydrogen bond, so their boiling points are lower than those of similar size amides.

Carboxylic Acid vs Amide – Boiling Points Carboxylic acid molecules are brought together via dispersion, dipole-dipole forces and most importantly, strong hydrogen bonds. However, amides generally have higher boiling points than carboxylic acids with similar molar mass, particularly primary and secondary amides.

Even the simplest carboxylic acid, formic acid, boils at 101 °C (214 °F), which is considerably higher than the boiling point of ethanol (ethyl alcohol), C2H5OH, which boils at 78.5 °C (173 °F), although the two have nearly identical molecular weights.

So, the H-bond formed in amines is weaker than that of formed in alcohol. Due to this reason, the boiling point of amines is less than that of alcohol. Hence, boiling point of amides is greater than carboxylic acids but Boiling point of amines is lower than that of alcohols.

Compared to amines, amides are very weak bases. While the conjugate acid of an amine has a pKa of about 9.5, the conjugate acid of an amide has a pKa around −0.5. Therefore, amides don’t have as clearly noticeable acid–base properties in water.

Amide has higher boiling point than carboxylic acid. Because amide will form more hydrogen bonds than carboxylic acid. Carboxylic acid has one hydrohen bond donor atom and two hydrogen bond acceptor atom while amide has two donor and two acceptor atoms.

The substituent -NH2 is called an amino group. Compounds with a nitrogen atom attached to a carbonyl group, thus having the structure R–CO–NR′R″, are called amides and have different chemical properties from amines.

Nonessential amino acids include: alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine. Conditional amino acids are usually not essential, except in times of illness and stress.

Basicity. Aniline is a weak base. Aromatic amines such as aniline are, in general, much weaker bases than aliphatic amines. Aniline reacts with strong acids to form the anilinium (or phenylammonium) ion (C6H5-NH3+).

As we might guess from considering electronegativities (estimated from positions in the periodic table), the N-H bond is more polar than the C-H bond and less polar than the O-H bond. The most important of these forces is called the hydrogen bond. The hydrogen bond is much weaker than a covalent bond.

Esters have the general formula RCOOR′, where R may be a hydrogen atom, an alkyl group, or an aryl group, and R′ may be an alkyl group or an aryl group but not a hydrogen atom.

Nitro compound, any of a family of chemical compounds in which the nitro group (―O―N=O) forms part of the molecular structure. The most common examples are organic substances in which a carbon atom is linked by a covalent bond to the nitrogen atom of the nitro group.

The amine functional group consists of an N atom bonded either to C or H atoms via σ bonds. Both the C-N and the N-H bonds are polar due to the electronegativity of the N atom. The trigonal pyramidal arrangement of bonds around nitrogen is shallower in aryl amines vs alkyl amines.

Hydrogen bonding in alcohols An alcohol is an organic molecule containing an -O-H group. Any molecule which has a hydrogen atom attached directly to an oxygen or a nitrogen is capable of hydrogen bonding. Ethanol, CH3CH2-O-H, and methoxymethane, CH3-O-CH3, both have the same molecular formula, C2H6O.

Amines are stronger bases than alcohols. Again we can use lone pair availability…. N is less electronegative than O so it is a better electron donor. Acidity increases down a group, so the thiol is a worse base than the alcohol….

amides are polar due to the carbonyl group, and the fact that nitrogen is pretty electronegative. ethers can be polar or they can be symmetrically non-polar.

The O-H bond is more in alcohol than carboxylic acid. This is because in carboxylic acid due to resonance, the oxygen atom in O-H gets positively charged, hence polarity decreases.

The carbonyl group (“carbon double bond oxygen”) is polar since oxygen is more electronegative than carbon and forms a partially charged dipole. Therefore, the dipole on N-H is much weaker than the dipole on O-H.

When 2 equally strong (electronegative) atoms are bound, the sharing of electrons will be equal between them. If a functional group is composed of an atom that has strong-weak bonds, the group will be polar.