Switching of Sulfonylation Selectivity by Nature of Solvent and Temperature: The Reaction of β‐Dicarbonyl Compounds with Sodium Sulfinates under the Action of Iron‐Based Oxidants

Abstract

Selectivity of sulfonylation of β‐keto esters with sodium sulfinates under the action of iron(III) salts as oxidants can be regulated by the type of solvent used and the reaction temperature. α‐Sulfonyl β‐keto esters are obtained when the process is conducted in THF/H2O solution at 40 °C. The change of the solvent to iPrOH/H2O and refluxing of a reaction mixture provides α‐sulfonyl esters – the products of successive sulfonylation‐deacylation. When β‐diketones are applied as starting materials, only α‐sulfonyl ketones are formed. The reaction pathway includes sulfonylation of dicabonyl compounds under the action of Fe(III) to form α‐sulfonylated dicarbonyl compounds, which are then attacked by a solvent as the nucleophile, resulting in the products of successive sulfonylation‐deacylation. Participation of the solvent in the reaction pathway determines the products structure.

Switchable Product Selectivity in Diazoalkane Coupling Catalyzed by a Two-Coordinate Cobalt Complex

“…Product selectivity is a critical property that defines the utility of a catalyst, and it is a primary consideration in the design of new catalytic processes. − Thus, an important aspect of catalyst discovery concerns the use of mechanistic information in tuning the reactivity of key intermediates to favor the generation of the desired product over possible side reactions. While the exclusive formation of a given product usually defines the effectiveness of a chemical transformation, the switchability of reaction pathways between different outcomes, depending on conditions such as exogenous additives, reaction temperature, irradiation wavelengths, and solvent identity, has attracted significant interest. − The prospect of obtaining different products from the same set of reactants and catalysts by simply changing reaction conditions suggests new directions for practical applications of catalysis in chemistry and chemical engineering.…”

Iron-Catalyzed, Site-Selective Difluoromethylthiolation (−SCF2H) and Difluoromethylselenation (−SeCF2H) of Unactivated C(sp3)–H Bonds in N-Fluoroamides

“…22 Subsequently, N-fluorotosylamide 1 was reduced by this Fe(II)L n complex A to produce FFe(III)L n C as well as amidyl radical D. 14 The latter radical went through an intramolecular 1,5-HAT to form the radical E, which could be trapped by PhSO 2 SCF 2 H to provide the observed C(sp 3 )− H difluoromethylthiolation product 2 and benzenesulfonyl radical F at the same time. Meanwhile, as reported by Terent'ev and coworkers, 20 the interaction of benzenesulfonyl radical F with B under the promotion of FFe(III)L n C gives rise to 1-(phenylsulfonyl)propan-2-one 6 and reforms the Fe(II)L n .…”

Synthesis and applications of sodium sulfinates (RSO2Na): a powerful building block for the synthesis of organosulfur compounds

“…The Terent'ev group examined the dramatic influence of the solvent and temperature for the regulated selective sulfonylation of β-ketoesters with sodium sulfinates in the presence of iron( iii ) salts ( Scheme 150 ). 215 Direct oxidative sulfonylation of different β-ketoesters with various aryl-substituted sulfinates in THF : H 2 O (2 : 1) at 40 °C led to a series of α-sulfonyl β-ketoesters in good to high yields. The successive deacylative-sulfonylation of aliphatic and aromatic dicarbonyl compounds with a range of sodium sulfinates in i-PrOH : H 2 O (2 : 1) under reflux (78 °C) resulted in the formation of different β-keto sulfones in satisfactory yields.…”