Gold(I)‐Catalyzed Nucleophilic Propargylation of Azinium Ions via Hydroxydihydroazine Intermediates

Smithson, Jack; O'Brien, Luke; Jones, Kieran D.; Argent, Stephen P.; Wheelhouse, Katherine M.; Woodward, Simon; Ermanis, Kristaps; Lam, Hon Wai

Abstract

The nucleophilic propargylation of azinium ions with a propargylboronate proceeds efficiently under gold(I) catalysis. A range of N-alkylated pyridinium, quinolinium, and pyrazinium ions undergo propargylation with good yields and high regioselectivities to give various functionalized 1,4-dihydropyridines, 1,2-dihydropyridines, 1,4-dihydroquinolines, 1,2-dihydroquinolines, and 4,5-dihydropyrazines. No allenylation side-products are observed. Density functional theory (DFT) calculations provided insight into the mechanisms of these reactions. Hydroxydihydroazine intermediates formed by the addition of LiOH to the azinium ions were found to be the reactive electrophiles in these reactions.

Citation

Smithson, J., O'Brien, L., Jones, K. D., Argent, S. P., Wheelhouse, K. M., Woodward, S., Ermanis, K., & Lam, H. W. (2025). Gold(I)‐Catalyzed Nucleophilic Propargylation of Azinium Ions via Hydroxydihydroazine Intermediates. Chemistry - A European Journal, https://doi.org/10.1002/chem.202404153

• Journal Article Type: Article
• Acceptance Date: Jan 8, 2025
• Online Publication Date: Jan 13, 2025
• Publication Date: Jan 13, 2025
• Deposit Date: Jan 25, 2025
• Publicly Available Date: Jan 27, 2025
• Journal: Chemistry – A European Journal
• Print ISSN: 0947-6539
• Electronic ISSN: 1521-3765
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1002/chem.202404153
• Public URL: https://nottingham-repository.worktribe.com/output/44538566
• Publisher URL: https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202404153