Stereochemistry of ring enlargements with bridged systems. Comparison of the nitrous acid deamination of endo- and exo-2-aminomethylbicyclo[3.2.1]octan-2-ol with the reaction between bicyclo[3.2.1]-octan-2-one and diazomethane

Abstract

The synthesis and nitrous acid deamination of exo- and endo-2-aminomethylbicyclo[3.2.1]octan-2-ol are described. The product distribution is markedly dependent on the amino-alcohol stereochemistry and comparison with the product distribution for the diazomethane ring enlargement of bicyclo[3.2.1]octan-2-one suggests that diazomethane attacks the carbonyl group preferentially from the exo-side (equatorial direction). A similar study with bicyclo[2.2.1]heptane systems is also reported.