107300-55-0Relevant academic research and scientific papers
1,3-Dipolar cycloaddition of nitrile oxides with unsymmetrically substituted norbornenes
Mayo, Peter,Hecnar, Tiffany,Tam, William
, p. 5931 - 5941 (2001)
1,3-Dipolar cycloadditions of nitrile oxides with unsymmetrically substituted norbornenes were investigated. The cycloadditions were found to be completely stereoselective, giving only the exo cycloadducts in moderate to good yields. Regioselectivities in the cycloadditions ranging from 50:50 to 100:0 were observed with various unsymmetrically substituted norbornenes.
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.
