ISSN:
0021-8383
Schlagwort(e):
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
LIS and X-Ray Investigations of the Structure of 1,5-Diaza-Bicyclo-[3,1,0]-hexanones-(2) Obtained by Irradiation of Pyrazolidone-(3)-azomethineimines1,5-Diaza-bicyclo-[3,1,0]-hexanones-(2) 2 are the photoproducts of pyrazolidone-(3)-azomethineimines 1. Generally they can exist in the exo-form or in the endo-form. 1H-n.m.r.-measurements of 2a-d show that neither at normal temperature (298 K) nor at low temperatures (213 K) an exo/endo mixture is formed photochemically. Therefore the conclusion is drawn that the photoreaction is stereospecific. Chemical shift calculations of the methyleneprotons and the methyl-protons in 2c and 2d using the ring current model and lanthanoide induced shifts (LIS) on 2d with Eu(fod)3 show that in solution the photoproducts have the exo-form. These results are in agreement with results of a single-crystal X-ray structure analysis on 2a.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/prac.19833250616
