“…(exo,exo)- (5,5) [Mf], 368 (19), 366 (17) (33), 118 (loo), 105 (34), 92 (44), 91 (85), 56 (28). -UV (1 a, 4a,4ap,5a, 8a,8ap, 9a, 9ap, 1 ( 1 S*,2R*,3R',4R*,aS*)-(3-(4-Brombenzoyl) bicyclo Umsetzung der y-Oxoketene 4g,h,i rnit BF3.OEt2 in Gegenwart von Norbornen (1 a,4a,4ap,5a,8a,Sap,9a,9ap,1 Oa,l Oa p) -Tetradecah ydro-9- (4nitrophenyl)-l2-oxo-lO-phenyE-lO,9-(epoxymethano)-1,4:5,8 455 (12) [M+], 361 (30), 334 (24), 333 (loo), 305 (13), 105 (67), 77 (19), 67 (13), 66 (12).…”