ISSN:
0947-3440
Schlagwort(e):
Oxanorbornadienes
;
Oxaquadricyclanes
;
[2 + 2] Photocycloaddition
;
Propellanes
;
Carbonyl ylides
;
Nitrile dipolarophiles
;
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
On photochemical excitation of the benzofuro-annulated oxanorbornadiene 10 in the presence of dipolarophiles the 1:1 addition compounds 11, 22, 23a,b, and 24, respectively, are formed as the only monomeric products. The mechanistic interpretation is based on a reaction sequence which involves [2 + 2] photocycloaddition to the oxaquadricyclane 12, 1,3-dipolar cycloreversion to the carbonyl ylide 13 and subsequent face-selective trapping by the corresponding dipolarophile. No indication of the transformation of 13 to the highly strained [3]3,6-oxepinophane 14 was obtained. With the formation of 11 one of the rare examples of the cycloaddition of a nitrile dipolarophile (i.e. acetonitrile) was uncovered.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/jlac.1995199508205
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