Utilization of Formic Acid as C1 Building Block for the Ruthenium‐Catalyzed Synthesis of Formaldehyde Surrogates

Abstract

Dialkoxymethanes are becoming increasingly important as fuel additives, formaldehyde surrogates, and chemical intermediates, but the effective synthesis remains challenging. Herein, the catalytic synthesis of dialkoxymethane products using a molecular catalyst is reported. The catalytic system, comprising the [Ru(triphos)(tmm)] in combination with the Lewis acid Al(OTf)3, enables the direct synthesis of dialkoxymethane products with formic acid as C1 building block in high to excellent turnover numbers.

Catalytic Reductive Alcohol Etherifications with Carbonyl‐Based Compounds or CO2 and Related Transformations for the Synthesis of Ether Derivatives

“…In these conditions, DMM was obtained with TONs up to 1076. Remarkably, it was showed that FA concentration in the methanolic solution had an important impact on the overall process [215] . A notable decrease in the DMM yield was detected when [FA]<3.4 m was employed, which limits the applicability of the process.…”

“…Last year, Klankermayer and co‐workers developed the only hydrogenative protocol for alcohol etherification using FA as C 1 feedstock (Scheme 37 ). [215] In this work, the authors employed Ru(Triphos)(tmm)/Al(OTf) 3 catalytic system (Scheme 35 A) for obtaining several dialkoxymethylene ethers from 1°/2° alcohols and FA. In these conditions, DMM was obtained with TONs up to 1076.…”

“…Remarkably, it was showed that FA concentration in the methanolic solution had an important impact on the overall process. [215] A notable decrease in the DMM yield was detected when [FA]<3.4 m was employed, which limits the applicability of the process. Despite this limitation, this is a very interesting protocol as FA is an environmentally benign reagent with easier handling and better storage properties than CO 2 .…”

Reaction Network Analysis of the Ruthenium‐Catalyzed Reduction of Carbon Dioxide to Dimethoxymethane

“…Previous studies focused on structural and electronic modifications of the catalyst, like interchanging the transition metal center, [10] varying the coordinating phosphorus moiety, [9] or introducing different hetero‐atoms in the apex position of the triphos ligand [11] . Furthermore, it was reported that formic acid can be employed as starting compound for the synthesis of DMM under the same catalytic conditions [12] . In addition, the ruthenium triphos formate complex has been identified as an active catalytic species and catalyst deactivation pathways can be suppressed by addition of formic acid and monodentate phosphine ligands, thus contributing to catalyst recycling [13] …”

“…[11] Furthermore, it was reported that formic acid can be employed as starting compound for the synthesis of DMM under the same catalytic conditions. [12] In addition, the ruthenium triphos formate complex has been identified as an active catalytic species and catalyst deactivation pathways can be suppressed by addition of formic acid and monodentate phosphine ligands, thus contributing to catalyst recycling. [13] Even though catalyst modification, reaction parameter optimization as well as recyclability studies were conducted to dramatically increase turnover numbers and selectivities, the kinetic parameters of the reaction network are not well investigated.…”