ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
1,2,3-Triazolidines by Cycloaddition of Azimines to OlefinesAzimines A can undergo [3+2]-cycloadditions with olefines B to give 1,2,3-triazolidines C, a class of hitherto unknown heterocycles. The three examples of this reaction realized here involved the azimine 1 with electron-withdrawing substituents and the olefines 2, 3 and 4 with an electron-donating substituent, yielding the cycloadducts 5,6 and 7. The triazolidine structure of 5 was established by an X-ray diffraction analysis. Characteristic for 5 are also: (a) that the three N-atoms are pyramidal (and thus centers of chirality), (b) that the five-membered heterocycle takes on a twist (half-chair) form, and (c) that the regioselectivity of the cycloaddition places the (E)-substituent of the olefine 2 vicinal to the terminal (Z)-substituent of the azimine 1. On this basis the constitutions of 6 and 7 are assigned. The spectral properties of the triazolidines 5, 6 and 7, including the 15N-NMR signals of one example, are compared with those of the related triazane 12.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19830660530
