Chapter 23 - Amines

neutral pH

neutral pH

Near ________ and in biological fluids, alkyl amines are protonated and positively charged.

Azides

________ can also be used to ring open epoxides before reducing them to produce amino alcohols with trans stereoselectivity.

Secondary

________ and tertiary amines are referred to as N- substituted primary amines, with the biggest group serving as the parent amine; the smaller groups bound to nitrogen are then referred to by the prefix N.

nitro substitution

The drop in basicity generated by ________ is caused by a combination of inductive and resonance effects, as demonstrated by comparing the pKa values of 3- nitroaniline and 4- nitroaniline conjugate acids.

Primary and Secondary

________ amines interact with solutes predominantly through hydrogen bonding, have significantly higher melting and boiling temperatures, and are more soluble in water than similar hydrocarbons.

electronegative sp2

Because the pyridine lone pair is in a moderately ________ orbital, the pKa of the conjugate acid of pyridine is 5.25, which is lower than that of an alkyl amine.

tertiary amine

When a(n) ________ is treated with hydrogen peroxide, an amine oxide is formed, which when heated yields an alkene and an N, N- dialkylhydroxyamine in a Cope elimination process.

N atom

Only one ________ in imidazole can be protonated since the lone pair on the other N atom is part of the aromatic p system and protonation would destroy the aromaticity.

similar alcohols

Amines have lower boiling points than ________ because H- N hydrogen bonds are weaker than H- O hydrogen bonds.

Nitrous acid

________, which is frequently generated in situ by combining NaNO2 with acid, interacts differently with amines depending on whether they are primary, secondary, tertiary, or aromatic.

Hofmann rule

The ________ is considered to be followed when eliminations generate mostly the least substituted alkene.

nitrogen atom

The ________ is present in heterocyclic amines.

alkyl groups

Because electron- releasing ________ stabilize the alkylammoniun ion, ________ make amines somewhat more basic.

Amines

________ react with strong acids to form water- soluble salts, which allows ________ to be separated from water- insoluble compounds.

Amines

________ can be synthesized by processes such as epoxide ring opening, addition of nitrogen nucleophiles to carbonyls followed by reduction, amide reduction, nitrile reduction, and arenes nitration followed by reduction.

Amines

________ are polar chemicals, and both primary and secondary amines may form intramolecular hydrogen bonds.