Mild and Low‐Pressure fac‐Ir(ppy)₃‐Mediated Radical Aminocarbonylation of Unactivated Alkyl Iodides through Visible‐Light Photoredox Catalysis

Abstract

A novel, mild and facile preparation of alkyl amides from unactivated alkyl iodides employing a fac-Ir(ppy)3 -catalyzed radical aminocarbonylation protocol has been developed. Using a two-chambered system, alkyl iodides, fac-Ir(ppy)3 , amines, reductants, and CO gas (released ex situ from Mo(CO)6 ), were combined and subjected to an initial radical reductive dehalogenation generating alkyl radicals, and a subsequent aminocarbonylation with amines affording a wide range of alkyl amides in moderate to excellent yields.

Visible‐Light Photocatalysis as an Enabling Tool for the Functionalization of Unactivated C(sp3)‐Substrates

“…[55] A range of substituted amides were formed from primary, secondary, and tertiary alkyl iodides and aliphatic or aromatic amines 36 together with carbon monoxide (CO) generated in situ from a solid CO source. The use of an Ir photocatalyst was instrumental in this reaction and afforded the key alkyl radical intermediates through the reductive activation mode.…”

Low‐Pressure Radical 11C‐Aminocarbonylation of Alkyl Iodides through Thermal Initiation

“…We initiated our studies by conducting a short screening study of aminocarbonylation conditions with CO (isotopically unmodified) to map out reaction parameters as a starting point for the corresponding 11 C‐aminocarbonylation reaction (Table ). Cyclohexyliodide and isopropylamine were used as model substrates by using a previously reported two‐chamber vial system, and the conversion was monitored by 1 H NMR spectroscopy. Cyclohexyl iodide, isopropylamine, AIBN, (TMS) 3 SiH, and triethylamine were added to chamber 1 in THF (3 mL) whereas Mo(CO) 6 was added to chamber 2 as the ex situ solid CO source.…”

“…Method A: To the CO‐releasing chamber ( C co ) of an H‐tube was added Mo(CO) 6 (0.6 mmol) and MeCN (3.0 mL). The reaction chamber ( C rxn ) was charged with alkyl iodide (0.3 mmol), amine (0.6 mmol), fac ‐Ir(ppy) 3 (2 mol‐%), Hantzsch ester (0.15 mmol), tributylamine (0.6 mmol), and MeCN (3.0 mL).…”

Sustainable Amidation Reactions – Recent Advances

“…L. Odell and co‐workers reported a novel synthesis of alkyl amides 41 using unactivated alkyl iodides 39 via iridium‐catalyzed aminocarbonylation reaction (Scheme ). This reaction consisted of the use of a two‐chambered system, with the first containing a fac‐Ir(ppy) 3 catalyst and the second contain a Mo(CO) 6 catalyst that allowed CO ex situ release.…”