Cycloaddition Cascades of Strained Alkynes and Oxadiazinones. (6th July 2021)

• Record Type: Journal Article
• Authors: Ramirez, Melissa; Darzi, Evan R.; Donaldson, Joyann S.; Houk, Kendall N.; Garg, Neil K.
• Is Part Of: Angewandte Chemie. Volume 133:Number 33(2021)
• Page Start: 18349
• Page End: 18356
• Publication Date: 2021-07-06
• Subjects: arynes -- cyclic alkynes -- cycloadditions -- density functional theory -- polycyclic aromatic hydrocarbons; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202105244
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: We report a computational and experimental study of the reaction of oxadiazinones and strained alkynes to give polycyclic aromatic hydrocarbons (PAHs). The reaction proceeds by way of a pericyclic reaction cascade and leads to the formation of four new carbon−carbon bonds. Using M06‐2X DFT calculations, we interrogate several mechanistic aspects of the reaction, such as why the use of non‐aromatic strained alkynes can be used to access unsymmetrical PAHs, whereas the use of arynes in the methodology leads to symmetrical PAHs. In addition, experimental studies enable the rapid synthesis of new PAHs, including tetracene and pentacene scaffolds. These studies not only provide fundamental insight regarding the aforementioned cycloaddition cascades and synthetic access to PAH scaffolds, but are also expected to enable the synthesis of new materials. Abstract : A computational and experimental study on the reaction of oxadiazinones and strained alkynes to give polycyclic aromatic hydrocarbons (PAHs) is reported. Mechanistic aspects of the reaction, such as why the use of non‐aromatic strained alkynes can be used to access unsymmetrical PAHs whereas the use of arynes leads to symmetrical PAHs, are investigated. Experimental studies enable the rapid synthesis of new PAHs, including tetracene and pentacene scaffolds.