4-allenylbromobenzene 、 tert-butyl 2-diazo-3,6-dioxoheptanoate 在
dirhodium(II)tetrakis[N-tetrachlorophthaloyl-(S)-tert-leucinate] 作用下,
反应 0.5h,
以71%的产率得到(1R,5R,7R)-7-(4-bromophenyl)-1-tert-butoxycarbonyl-5-methyl-6-methylene-8-oxabicyclo[3.2.1]octan-2-one