呋喃 、
1'-cyanovinyl (1S,5R,7S)-3-ethyl-2-oxo-6,8-dioxa-3-azabicyclo<3.2.1>octane-7-exo-carboxylate 在
4 A molecular sieve 、 zinc dibromide 作用下,
反应 168.0h,
以17%的产率得到(1'R,2'S,4'R)-2'-exo-cyano-7'-oxabicyclo<2.2.1>hept-5'-en-2'-endo-yl (1S,5R,7S)-3-ethyl-2-oxo-6,8-dioxa-3-azabicyclo<3.2.1>octane-7-exo-carboxylate