Photoinduced Remote C(sp³)-H Phosphonylation of Amides

Area of Science:

• Organic Chemistry
• Catalysis
• Synthetic Methodology

Background:

• C-H bond functionalization is a crucial area in organic synthesis.
• Developing methods for phosphonylation of unactivated C(sp3)-H bonds remains challenging.

Purpose of the Study:

• To report a novel protocol for the phosphonylation of unactivated C(sp3)-H bonds.
• To achieve high yields of gamma-phosphonylated amides under mild conditions.

Main Methods:

• Visible-light photoredox catalysis utilizing 1,2,3,5-tetrakis(diphenylamino)-4,6-dicyanobenzene (4DPAIPN) as a catalyst.
• Reaction between N-((4-cyanobenzoyl)oxy)alkanamides and 9-fluorenyl o-phenylene phosphite at room temperature.

Main Results:

• Achieved satisfactory yields of gamma-phosphonylated amides.
• Demonstrated broad substrate scope and wide functional group compatibility.
• The reaction proceeded efficiently at room temperature under visible light.

Conclusions:

• The developed protocol offers an unprecedented and efficient route for phosphonylation of unactivated C(sp3)-H bonds.
• This method provides a valuable tool for synthesizing complex phosphonylated compounds.
• The catalytic system shows high efficiency and broad applicability in organic synthesis.