Synthesis of novel carbo- and hetero-polycycles. Part 7. Synthesis of 6-azatricyclo[6.3.1.0]dodecane and 5-azatricyclo[5.3.1.1]dodecane derivatives via intramolecular cycloaddition of N-{(endo-bicyclo[3.3.1]non-6-en-3-yl)methyl}nitrones

Abstract

The Intramolecular cycloaddition of N-{(endo-bicyclo[3.3.1]non-6-en-3-yl)methyl}nitrones (4a–c), generated in situ from the corresponding hydroxylamine with formaldehyde, benzaldehyde, and 2-furaldehyde, afforded both regioisomers (5a–c) and (6a–c). The regioisomeric ratios were dependent on the nitrone's α-substituent. Reductive cleavages of (5), (6), or their methiodides give the corresponding azatricyclododecane derivatives (9a, b) and (10, b).