Iron‐Catalyzed Stereoselective Cross‐Coupling Reactions of Stereodefined Enol Carbamates with Grignard Reagents

Abstract

A practical and highly stereoselective iron-catalyzed cross-coupling reaction of stereodefined enol carbamates and Grignard reagents to yield tri- and tetrasubstituted acrylates is reported. A facile method for the stereoselective generation of these enol carbamates has also been developed.

Fe‐Catalyzed Cross‐Coupling Reaction of Vinylic Ethers with Aryl Grignard Reagents

“…Not only due to the big advantage of iron as an abundant and economical resource, Fe has attractive features as catalysts and has been employed for the cross‐coupling reaction of oxygen‐containing substrates, including sulfonates, sulfamates,, esters, carbamates, and phosphates . However, the Fe‐catalyzed cross‐coupling reaction of ethers, a simplest unactivated oxygen‐containing family, has not yet been accomplished to date (Scheme b).…”

On the Use of Iron in Organic Chemistry

“…A variety of alkyl and aryl Grignard reagents could be applied and it was demonstrated that the protocol can be readily performed on a gram-scale. In 2016, the group of Frantz reported on a highly stereoselective iron-catalyzed cross coupling using FeCl 3 to couple Grignard reagents and enol carbamates (Scheme 15) [45]. Many functional groups, such as ethers, silanes, primary bromides, alkynes and alkenes, were tolerated.…”

Stereodivergent synthesis of β-iodoenol carbamates with CO2viaphotocatalysis

“… 6 Organic carbamates constitute an important class of compounds, which are widely used in agrochemicals, 7 pharmaceuticals 8 and as intermediates in organic synthesis. 9 Traditional methods for the preparation of carbamates are mainly based on the use of toxic phosgene and its derivatives, which are environmentally unfriendly. 10 In the past decades, many phosgene-free protocols have been explored for the synthesis of carbamates.…”