BrCH2−CH2OH\mathrm{BrCH}_{2}-\mathrm{CH}_{2} \mathrm{OH}BrCH2−CH2OH
BrCH2−CH2Br\mathrm{BrCH}_{2}-\mathrm{CH}_{2} \mathrm{Br}BrCH2−CH2Br
HCHO\mathrm{HCHO}HCHO
CH3CHO\mathrm{CH}_{3} \mathrm{CHO}CH3CHO