Discussion: amines

Amine nomenclature

diisopropylamine pyrrole

nicotine histamine pyrrolidine

Formation of amines

triethylamine

Mechanism for LAH reduction of amides

1-methylpiperidine

One equivalent

SN2 is faster the more R groups on NHow do you improve selectivity??

Still mixtureNeed a base to remove protons to get to quaternary product

Poor selectivity save for quaternary product and for primary amines from ammonia.

Only good for primary amines

Reduction of nitriles with LiAlH4: MECHANISM

Gabriel Synthesis of primary amines

Name?

Product(s)?

Reactions of Amines

• Acid-base• Formation of amide• Imines and enamines• Formation of urea from isocyanate• Hoffmann elimination and substitution

reactions

Higher the pKa of conjugate acid, the more basic the amine

Which is the strongest base? Which is the weakest base?

Which conjugate base is more basic (stronger)?

Which conjugate base is more basic (stronger)?

Based on the pKa of imidazolium ion above, describe the what the imidazole group in the histidine residue in a peptide would be under physiological conditions (pH 7).

Formation of amide

Acetamides