Amineurs

Amineurs, also known as aminating reagents, are chemical reagents or catalysts used to introduce amino groups into organic substrates. They enable the formation of C–N bonds and the synthesis of primary, secondary, and tertiary amines, which are widespread in pharmaceuticals, agrochemicals, and materials. Amine introduction can proceed through several general strategies, including electrophilic amination, nucleophilic amination, and nitrene-transfer.

Electrophilic amination uses reagents that deliver a highly reactive amino unit to electrophilic substrates, often enabling bond construction on activated arenes, alkenes, or enolates. Nucleophilic amination relies on ammonia or amines acting as nucleophiles toward activated carbon centers or leaving groups, frequently under catalytic or activation conditions. Nitrene-transfer involves generating a reactive nitrene from precursors such as azides or iminoiodinanes, which inserts into C–H or C=C bonds or couples with directing groups to form amines.

Prominent methods in contemporary synthesis include the Buchwald–Hartwig amination, a transition-metal–catalyzed cross-coupling that forms aryl- or vinyl-amines from aryl halides or related substrates with amines; direct C–H amination using nitrene equivalents under metal catalysis; and reductive or transfer‑based aminations that convert carbonyl-derived intermediates into amines via imine or iminium pathways. Specialized amination reagents include azodicarboxylates, sulfonyl azides, and various hydroxylamine derivatives, each providing different reactivities and selectivities for diverse substrates.

Safety and scope: many amination reagents are toxic or reactive, requiring careful handling, solvent choice, and operational controls. Substrate compatibility and reaction conditions strongly influence outcomes, guiding ongoing research toward broader applicability and greener practices.

See also: amines, amination, Buchwald–Hartwig amination, C–N bond formation, nitrene transfer.