16179-36-5

Fast addition of highly polar organometallic reagents (RMgX/RLi) to cyclic carbonates (derived from CO2 as a sustainable C1 synthon) has been studied in 2-methyltetrahydrofuran as a green reaction medium or in the absence of external volatile organic solvents, at room temperature, and in the presence of air/moisture. These reaction conditions are generally forbidden with these highly reactive main-group organometallic compounds. The correct stoichiometry and nature of the polar organometallic alkylating or arylating reagent allows straightforward synthesis of: highly substituted tertiary alcohols, β-hydroxy esters, or symmetric ketones, working always under air and at room temperature. Finally, an unprecedented one-pot/two-step hybrid protocol is developed through combination of an Al-catalyzed cycloaddition of CO2 and propylene oxide with the concomitant fast addition of RLi reagents to the in situ and transiently formed cyclic carbonate, thus allowing indirect conversion of CO2 into the desired highly substituted tertiary alcohols without need for isolation or purification of any reaction intermediates.

(Poly)glycerol monoethers were synthesized in good yield and selectivity by the catalytic reductive alkylation of glycerol, diglycerol, and triglycerol with readily available, cheap and/or bio-sourced carboxylic acids. The reaction was catalyzed by 1 mol % of Pd/C under 50 bar H2 using an acid ion-exchange resin as a recyclable cocatalyst. The catalytic system was recycled several times, and a mechanism is proposed for this transformation.

The radical cations of the ethylene ketals of some cyclic and bicyclic ketones are generated by single electron transfer to excited benzene-1,2,4,5-tetracarbonitrile (TCB).Their fragmentation yields 1,5- and 1,6-distonic radical cations, which add to TCB(-.) to give alkyl>benzenetricarbonitriles.The reduction of the radical center occurs only to a small extent, and is enhanced in the presence of dodecylmercaptan, in the case of hindered radicals.The reaction of the camphor ethylene ketal (both alkylation of TCB and reduction) occurs with total diastereoselectivity at the reacting radical center.