gem‐Dichlorocyclopropanation of Dicarbonyl Derivatives

Abstract

An ovel methodology for the 1,1-dichlorocyclopropanation of dicarbonyl conjugated olefins was described. The developed protocol is simple and uses readily accessible starting materials, allowing the isolation of the desired adducts in moderate to excellent yields (up to 99 %). Furthermore, the reaction tolerated scale up to the gram scale;thus highlighting the syntheticp otentialo ft his transformation.Controle xperimentsa nd DFT studies revealed that the reaction proceeded through aM ichael-initiated ring-closure process, in which reactiont emperature played ac rucial role. Finally,t hese gem-dichlorocyclopropanes were also employed in the preparation of at risubstituted naphthyl derivative and ad iastereoselective reduction was also demonstrated.Scheme1.Previousstudies and our proposal for the gem-dichlorocyclopropanationofo lefins. TMS = trimethylsilyl.[a] G.The reaction mixture was purified through column chromatography on silica gel (elution:h exane/CH 2 Cl 2 1:1) to afford product 2l as ac olorless oil (59 mg, 99 %).

Diverse 3-Methylthio-4-Substituted Maleimides through a Novel Rearrangement Reaction: Synthesis and Selective Cell Imaging

“…Initially, the decarboxylation of the trichloroacetate salt leads to the formation of the [CCl 3 ] − anion. This decarboxylation readily occurs in DMSO, especially when the reaction mixture is heated, as we have previously demonstrated. − Next, this anion deprotonates the acidic imide group, producing chloroform as a byproduct and a potassium imide salt ( A and B ). The ring opening results in the formation of isocyanate intermediate C .…”

Electron-Donor–Acceptor Complex-Enabled Flow Methodology for the Hydrotrifluoromethylation of Unsaturated β-Keto Esters

“…The dicarbonyl compound 1a was prepared according to the literature protocol through oxidation of the corresponding Morita–Baylis–Hillman adduct . Next, a series of optimization reactions were carried out under batch conditions (for full details, see the Supporting Information).…”

“…The dicarbonyl compound 1a was prepared according to the literature protocol through oxidation of the corresponding Morita−Baylis−Hillman adduct. 13 Next, a series of optimization reactions were carried out under batch conditions (for full details, see the Supporting Information). Although initially we considered the use of diverse photocatalysts, such as the commercially available [Ru(bpy) 3 (PF 6 ) 2 ], the isolated yields were only low to moderate (up to 48%).…”