Cyanomethyl Anion/Carbon Dioxide System:  An Electrogenerated Carboxylating Reagent. Synthesis of Carbamates under Mild and Safe Conditions

Abstract

A new carboxylating reagent ((-)CH(2)CN/CO(2)) was obtained by bubbling CO(2) in a CH(3)CN-TEAP (tetraethylammonium perchlorate) solution previously electrolyzed under galvanostatic control. Organic carbamates were isolated from these solutions after addition of amines and an alkylating agent. In this paper, we describe the optimized conditions for the electrochemical synthesis of carbamates from amines and CO(2), in mild and safe conditions, without any addition of bases, probases, or catalysts. Carbamates were isolated from primary and secondary aliphatic amines in high to excellent yields and from aromatic amines in moderate yields (dependent on the nucleophilicity of the nitrogen atom).

The First Cyanomethyl Complex of Gold, Synthesized by Reaction of a AuI Complex with Acetonitrile in the Presence of a New Guanidine N‐Superbase

“…[5] The cyanomethyl anion can also be generated in larger quantities by galvanostatic electrolysis of CH 3 synthesis, [6] e. g. for the synthesis of carbamates under mild and safe conditions. [7] Metal complexes featuring cyanomethyl ligands are also accessible via oxidative addition reactions. Hence oxidative addition of ClCH 2 4 ]Cl is dissolved in neat CH 3 CN at room temperature.…”

An Electrochemical Alternative Approach to the Cyclization of Alkynes Bearing Proximate Malonyl Moieties

“…The yield of 4a depends on the amount of the electricity supplied during the electrolyses (Q), increasing with Q up to a value of 2.0 F mol -1 with reference to substrate 1a. As reported in our previous works, [13,16] the electrogeneration of the cyanomethyl anion is quite a complex process that also involves the formation of 3-aminocrotonitrile anion ( also play a pivotal role in determining the reaction outcome. The best results were observed with use of acetonitrile as solvent and tetraethylammonium tetrafluoroborate (TEATFB) as supporting electrolyte.…”

In situ FT-IR and ex situ EPR analysis for the study of the electroreduction of carbon dioxide in N,N-dimethylformamide on a gold interface

“…Carbamate synthesis N-Cyclohexyl ethyl carbamate was chosen as a model compound because the synthesis of this carbamate starting from the electrochemical reduction of CO 2 had been well established [17,19]. For the sake of comparison, four other carbamates, not previously reported, were also obtained in good yields following the same procedure.…”

“…Equations showing the synthesis reaction of carbamates according to reported procedures [17,19] and to the present work are given in Scheme 1. From the electrochemical process represented by Eq.…”

“…More recently [19], the synthesis of alkyl carbamates through carbon dioxide reduction has been described as being promoted by the cyanomethyl anion. This anion was formed in acetonitrile with platinum as a cathode.…”