1-羟环丁-1-烯-3,4-二酮

双环[3,2,0]庚-2-烯-6-酮

2,2-dichloro-3-phenylcyclobutan-1-one

9,9-dichlorobicyclo[6.2.0]dec-4-en-10-one

2,2-dichloro-3-(phenylmethoxymethyl)cyclobutan-1-one