107300-58-3Relevant academic research and scientific papers
1,3-Dipolar Cycloadditions with the Keto- and Spirocyclopropane-Substituted Norbornenes Bicyclohept-5-en-2-one and Spirohept-5-ene-2,1'-cyclopropane>
Adam, Waldemar,Carballeira, Nestor,Craemer, Elisabeth,Lucchini, Vittorio,Peters, Eva-Maria,et al.
, p. 695 - 704 (2007/10/02)
The keto- and spirocyclopropane-substituted norbornenes K and S, respectively, were submitted to 1,3-dipolar cycloaddition with diazomethane (1), diphenyldiazomethane (2), phenyl azide (3), and benzonitrile oxide (4) leading in equal proportions to the corresponding regioisomers of the cycloadducts K-2a,b through K-4a,b and S-1a,b through S-4a,b.The keto and spirocyclopropane substituents perturb the ? systems of these norbornenes too weakly to sense any significant regioselectivity for the 1,3-dipoles employed here.A combination of NOE differential 1H-NMR spectroscopy and X-ray analysis was essential to assign the structures of these regioisomers.
