The azabicyclo [3.2. 0] heptan-7-ones 4, 10, 16 and 24 have been prepared from pyrrole. The same general approach has been used for all these derivatives; namely, substitution of pyrrole at the 2-and 5-carbon atoms, catalytic hydrogenation to produce pyrrolidine-2-acetic acid derivatives, and cyclisation using tris (1, 3-dihydro-2-oxobenzoxazol-3-yl) phosphine oxide 6. The catalytic hydrogenation of 2, 5-disubstituted pyrroles gives only the ...
