Synthesis of tetrasubstituted alkenyl nitriles via cyanocarbene addition of [1.1.1]propellane

Abstract

Herein, we report the metal-free synthesis of methylenecyclobutane containing tetrasubstituted alkenyl nitriles via a strain-release driven addition reaction of [1.1.1]propellane under mild conditions. Using this strategy, TMSN3 was shown to...

Photocatalyzed Dual Strain Release of [1.1.1]Propellane with Diazo Compounds

“…Notably, this process entails the simultaneous cleavage and formation of multiple C–C bonds in a single step. Furthermore, it should be mentioned that a metal-free three-component reaction, involving hypervalent iodine­(III) alkyne species, [1.1.1]­propellane, and trimethylsilylazide, was reported to proceed through cyanocarbene intermediates …”

Three-Component Cyclobutylation via Silver(I)-Catalyzed Carbene Transfer Reactions with [1.1.1]Propellane

“…From the perspective of another mode of reactivity, the presence of inverted bridgehead carbon atoms and a weak central C–C bond in [1.1.1]­propellane has attracted interest. Its unique reactivity with various nucleophiles and radicals , provides access to bicyclo[1.1.1]­pentane derivatives (BCPs). Owing to the distinctive properties of the C–C central strained bond in [1.1.1]­propellane, the nucleophilic addition of anions (e.g., organometallic reagents and carbanions) to [1.1.1]­propellane parallels a standard S N 2 reaction pathway.…”

Synthesis of Imidized Cyclobutene Derivatives by Strain Release of [1.1.1]Propellane

“…Meanwhile, Aggarwal’s group produced methylenespiro[2.3]­hexane derivatives through nickel-catalyzed cyclopropanation reactions with [1.1.1]­propellane (Scheme a) . Recently, our group has reported cyanocarbene species generated by TMSN 3 and hypervalent iodine­(III) alkyne reagents could react with [1.1.1]­propellane to form cyclobutane-containing alkenyl nitriles (Scheme b) …”

“…Given the importance of imides in biologically active natural products and various pharmaceuticals, we devoted significant efforts to develop an efficient method for the production of imidized methylene cyclobutenes. Based on the above-mentioned literature reports and our previous work, , we originally speculated that the methylene cyclobutyl cation intermediate generated by [1.1.1]­propellane would react with nitriles to form a nitrilium ion intermediate. This intermediate may then react with carboxylic acid to afford an acyl imidate with a subsequent Mumm-type rearrangement to form imidized methylene cyclobutenes (Scheme c).…”