Isoquinolinium N-Arylimides and Electron-Deficient Ethylene Derivatives

✍ Scribed by Rolf Huisgen; Robert Temme

• Book ID: 102657816
• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 738 KB
• Volume: 1998
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/(sici)1099-0690(199802)1998:2<387::aid-ejoc387>3.0.co;2-j

✦ Synopsis

The 1,3-cycloadditions of isoquinolinium N-phenylimide (2a) med with dimethyl fumarate and maleate. The configurations were elucidated by 1 H NMR analysis, which likewise pro-and N-(2-pyridyl)imide (2b) to twelve α,β-unsaturated carboxylic esters and nitriles proceeded at room temp. with high vided the clue to the favored conformation of the tricyclic system. The N-arylimides 5 do not react with ethylene, but yields; the reactions furnished tetrahydropyrazolo[5,1-a]isoquinoline derivatives and could be visually followed by the the formal ethylene adducts were accessible from the cycloadducts of 5a,b to triphenylvinylphosphonium bromide by loss of the red color. In this class of azomethine imines, the imide nitrogen of 2 is the nucleophilic center which deter-alkaline cleavage. The statistical analysis of the δ H values of 39 cycloadducts provided a consistent set of substituent mines the regiochemistry of the additions to methyl acrylate, acrylonitrile, and their α-methyl and α-chloro derivatives. increments for the pyrazolidine protons. The diastereoselectivity is low; pairs of adducts were also for-