o If another functional groups or a-CHo are present ORGANIC CHEMISTRY Chapter 16 and the doubly bonded oxygen must be considered a substituent, the prefix oxo-is used CH3 CH2-C-CH2CHo CH2 CH,C-CH,CH,CO,H 3-Oxopentanal 4-0xohexanoic acid 3-氧代戊醛 4-氧代已酸 CHO 2'-Oxocyclohexanecarbaldehyde 2-氧代环己烷甲醛 Department of Chemistry, Xiamen UniversityORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 If another functional groups or a –CHO are present and the doubly bonded oxygen must be considered a substituent, the prefix oxo- is used. CHO O 2'-氧代环己烷甲醛 2'-Oxocyclohexanecarbaldehyde CH3CH2 C CH2CHO O 3-氧代戊醛 3-Oxopentanal CH3CH2 C CH2CH2CO2H O 4-Oxohexanoic acid 4-氧代己酸