Intramolecular heterocyclization and cyclopalladation of selenoanisole substituted propargyl imines: Synthesis and reactivity of Pd–C bond towards alkynes

Trifluoroacetimidoyl halides: a potent synthetic origin

“…The cyclopalladated benzoselenophenes were readily constructed from the intramolecular cyclization of selenoanisolesubstituted propargyl imines in the presence of stoichiometric amounts of dichorobis(-triphenylphosphine)palladium(II) in dry THF (Scheme 42). 60 The reactivity of cyclopalladated benzoselenophene complex was further explored via the insertion of different alkynes into the Pd-C bond of dimeric cyclopalladated benzoselenophenes to build benzoseleno[2,3-c]-pyridinones. The results demonstrated that the cyclopalladated heterocycles could be utilized to assemble various fused heterocycles through insertion reactions.…”

Recent Advances in the Synthesis of Selenophenes and Their Derivatives

“…After, the electron-rich selenium atom attacks the activated triple bond, with concomitant removal of the methyl group via an S N 2 nucleophilic displacement, which promotes it by the chloride anion present in the reaction medium, to give the product 142 (Scheme 94). In 2014, was described the intramolecular hetero-cyclization and cyclopalladation of selenoalkyne-substituted propargyl imines 141, for the synthesis benzoselenophene[2,3c]pyridinones 142 [178]. In order to promote this reaction, the palladations of ortho-selenoanisole perfluoro propargyl imines 141 was performed using a stoichiometric amount of dichorobis(triphenylphosphine)palladium(II) in dry THF, for 2 h at 0 °C, producing the respective benzoselenophene-based palladacycles 142a-c in 70-85% yields (Scheme 94).…”

“…In 2014, was described the intramolecular hetero-cyclization and cyclopalladation of selenoalkyne-substituted propargyl imines 141 , for the synthesis benzoselenophene[2,3- c ]pyridinones 142 [ 178 ] . In order to promote this reaction, the palladations of ortho -selenoanisole perfluoro propargyl imines 141 was performed using a stoichiometric amount of dichoro-bis(triphenylphosphine)palladium(II) in dry THF, for 2 h at 0 °C, producing the respective benzoselenophene-based palladacycles 142a - c in 70–85% yields ( Scheme 94 ).…”

The Construction of Nitrogen‐Containing Heterocycles from Alkynyl Imines

“…A two‐step reaction for the construction of benzoseleno/thieno [2,3‐ c ] pyridinones was presented by Likhar's group (Scheme 35). [53] The cyclopalladated benzoseleno/thienophenes were readily prepared from the intramolecular cyclization of selenoanisole‐substituted propargyl imines in the presence of stoichiometric amounts of dichorobis(triphenylphosphine)palladium(II). The reactivity of cyclopalladated benzoseleno/thienophenes was further explored via the insertion of different alkynes into the Pd−C bond of dimeric cyclopalladated benzoseleno/thienophenes to build benzoseleno/thieno [2,3‐ c ] pyridinones.…”