A green, efficient reductive N-formylation of nitro compounds catalyzed by metal-free graphitic carbon nitride supported on activated carbon

Catalyst-Free N-Formylation of Amines Using Formic Acid as a Sustainable C1 Source

“…The yield can be increased to 68% when the amount of HCOOH was increased to 4 mmol (entry 10), suggesting that formic acid serves as both a carbonyl reagent and reducing agent. 44,45 The substrate range was expanded by using the optimized reaction conditions. Various types of amines were effectively converted into formamides with excellent yields (Scheme 1).…”

“…These results indicated that formic acid acts as both a carbonyl reagent and reducing agent. 44,45 Considering that aniline and HCOOH reacted to form N-methylformanilide 22a, a controlled experiment was performed with the reaction of benzaldehyde and 22a. Benzaldehyde and 22a were found not to react (Scheme 3, eq 4), further confirming that imine was the intermediate in the reaction.…”

“…Furthermore, the three-component tandem reaction of aniline, benzaldehyde, and formic acid was investigated, and a 47% yield of formamide was obtained for this reaction (entry 9). The yield can be increased to 68% when the amount of HCOOH was increased to 4 mmol (entry 10), suggesting that formic acid serves as both a carbonyl reagent and reducing agent. , …”

Visible-light-induced photocatalytic reductive carbonylation of nitroarenes using formic acid as a hydrogen source over a water-dispersible CTF-based palladium catalyst

“…11,12 Thus far, several studies have been reported on the one-pot synthesis of N-formamides from nitroarenes using HCOOH or its derivatives. 5,[13][14][15][16] Given the fact that a selective decomposition of HCOOH to H 2 + CO 2 and the use of CO 2 as a formylation source thermodynamically are feasible (ΔG 298K = −35 kJ mol −1 ), it requires activation energy, which is generally provided through thermal energy and a suitable catalyst. 17,18 However, using light energy as an energy source is a much more sustainable process and can answer the energy crisis and mitigate environmental threats.…”

“…11,12 Thus far, several studies have been reported on the one-pot synthesis of N -formamides from nitroarenes using HCOOH or its derivatives. 5,13–16…”