Formic acid disproportionation into formaldehyde triggered by vanadium complexes with iridium catalysis under mild conditions in N-methylation

Abstract

Formaldehyde (CH2O) has been used as a key platform reagent in the chemical industry for many decades. In the current stage, the industrial production of CH2O mainly depends on the...

Utilization of renewable formic acid from lignocellulosic biomass for the selective hydrogenation and/or N‐methylation

“…of renewable HCO 2 H contained in wheat straw HOAS with 1 mol % of 2 d, 4 a was obtained in 91 % yield in 20 h. [7] Gram-scale N-methylation of 1 a afforded 4 a in 91 % yield. [7] The substrate scope was investigated (Scheme 3). Various substituents on different positions of quinoline were studied.…”

“…of renewable HCO 2 H with lower reaction efficiency should attribute to the further Nmethylation. [7] To demonstrate the potential application of the hydrogenation of quinoline, the gram-scale reaction was conducted by using quinoline 1 a as a substrate. With 0.25 mol % 2 d, 0.8 g of 3 a was obtained in 81 % yield by using 1.0 g wheat straw for production of renewable HCO 2 H (Table 1, entry 20).…”

“…Third, mercury was added after 1 h of the reaction, 3 a was obtained in the yield of 43 %, 60 %, 86 % after 2 h, 3 h, 5 h, in comparison with the yield of 45 %, 64 %, 87 % after 2 h, 3 h, 5 h without mercury, respectively. The standard mercury poisoning experiments were also carried out for the N-methylation of quinoline 1 a, [7] indole 5 a and aniline 7 a'. 4 a, 6 a, 8 a, were obtained in the yield of 87 %, 76 %, 92 %, in comparison with the yield of 91 %, 81 %, 91 % under standard conditions, respectively.…”

“…The gram-scale reaction was also demonstrated. [7] Herein, we report efficient utilization of renewable HCO 2 H from lignocellulosic biomass, wheat straw, for hydrogenation and further N-methylation of various quinolones and the derivatives, various indoles under mild conditions (Scheme 1a and 1b). Meanwhile, N-methylation of various anilines is also developed under mild conditions (Scheme 1c).…”

Metal-Free Hydroxymethylation of Indole Derivatives with Formic Acid as an Alternative Way to Indirect Utilization of CO2

“…In most cases, transition-metal catalysts are essential to the aforementioned conversions, and the alkylation reagents are limited to carboxylic acids. With our continuing interest in the valorization of formic acid (HCOOH) and considering the high efficiency of reductive amination, ,, we envisaged to develop the hydroxymethylation of indole derivatives using HCOOH as the alkylation reagent. Thus, this protocol could achieve the selective indole N-alkylation and utilization of the renewable resource HCOOH as a C1 synthon for reductive amination simultaneously.…”