The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity an...Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity and diversity.To the best of our knowledge,there is only one report on photoredox-catalyzed three-component DCFs with malonates through the radical−radical cross-coupling,while photoredox-catalyzed radical-polar crossover(RPC)-type DCFs with malonates were still rare.Herein,we describe a redox-neutral RPC-type 1,2-dialkylation of styrenes with malonates and aldehydes through the synergistic Brønsted base/photoredox catalysis system.This transition-metal-free strategy provides an efficient and clean approach to a broad variety ofδ-hydroxy esters and also features exceptionally mild conditions,wide compatibility of substrate scope and functional groups,and high atomic economy.Moreover,three-component 1,2-alkylacylation from the same starting materials was achieved in one-pot manner through such RPC-type coupling and subsequent two-electron oxidation process,providing a set ofδ-keto esters of interest in pharmaceutical research.展开更多
The solid condensation of isopropylidene malonate with aromatic aldehydes were carried out by grinding at room temperature or heating at 110～120 ℃ to give 5 arylidene 2,2 dimethyl 1,3 dioxane 4,6 dione . Both condit...The solid condensation of isopropylidene malonate with aromatic aldehydes were carried out by grinding at room temperature or heating at 110～120 ℃ to give 5 arylidene 2,2 dimethyl 1,3 dioxane 4,6 dione . Both conditions afford the condensation high reaction activity. The yield of the product under grinding for 20 min followed by standing for 48 h at room temperature is 56%～80% and that by heating at 110～120 ℃ for 12 min is 55%～74%, respectively.展开更多
文摘The condensation of aromatic aldehydes with isopropylidene malonate or 5,5-dimethyl-1,3-cyclohexanedione is carried out by DMF as solvent without catalyst.
基金supported by the National Natural Science Foundation of China(Nos.22101237,22171233)the Science and Technology Program of Sichuan Province(No.2022NSFSC1219)+1 种基金the Science and Technology Program of Luzhou City(Nos.2021-SYF-34,2023LZXNYDJ019)and the Open Project Program of Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province(No.HYX21003).
文摘Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity and diversity.To the best of our knowledge,there is only one report on photoredox-catalyzed three-component DCFs with malonates through the radical−radical cross-coupling,while photoredox-catalyzed radical-polar crossover(RPC)-type DCFs with malonates were still rare.Herein,we describe a redox-neutral RPC-type 1,2-dialkylation of styrenes with malonates and aldehydes through the synergistic Brønsted base/photoredox catalysis system.This transition-metal-free strategy provides an efficient and clean approach to a broad variety ofδ-hydroxy esters and also features exceptionally mild conditions,wide compatibility of substrate scope and functional groups,and high atomic economy.Moreover,three-component 1,2-alkylacylation from the same starting materials was achieved in one-pot manner through such RPC-type coupling and subsequent two-electron oxidation process,providing a set ofδ-keto esters of interest in pharmaceutical research.
文摘The solid condensation of isopropylidene malonate with aromatic aldehydes were carried out by grinding at room temperature or heating at 110～120 ℃ to give 5 arylidene 2,2 dimethyl 1,3 dioxane 4,6 dione . Both conditions afford the condensation high reaction activity. The yield of the product under grinding for 20 min followed by standing for 48 h at room temperature is 56%～80% and that by heating at 110～120 ℃ for 12 min is 55%～74%, respectively.
