ORGANIC CHEMISTRY Chapter 8 8.9 Divalent Carbon Compounds Carbenes 卡宾 Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 8 8.9 Divalent Carbon Compounds: Carbenes 卡宾
ORGANIC CHEMISTRY Chapter 8 o There is a group of compounds in which carbon forms only two bonds These neutral divalent carbon compounds are called carbenes o Most carbenes are highly unstable compounds that are capable of only fleeting existence Soon after carbenes are formed they usually react with another molecule RC° Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 8 There is a group of compounds in which carbon forms only two bonds. These neutral divalent carbon compounds are called carbenes. Most carbenes are highly unstable compounds that are capable of only fleeting existence. Soon after carbenes are formed they usually react with another molecule. R2C
ORGANIC CHEMISTRY Chapter 8 8.9a Structure and Reactions of methylene h CHOC=O CH2 CO CH CH, t n2 RI (4 R R 单线态三线态 Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 8 8.9A Structure and Reactions of Methylene CH2 C O CH2 + CO CH2 N+ N− hv hv CH2 + N 2 C R R R C R 单线态 三线态
ORGANIC CHEMISTRY Chapter 8 H C-C. + CH 2 C-C CH CH CH (A-2-Butene Methylene CH cis-1, 2-Dimethylcyclopropane Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 8 H C CH3 C H CH3 H C CH3 C HCH3 CH2 H C CH3 C H CH3 CH2 + CH2 Methylene cis-1,2-Dimethylcyclopropane (Z)-2-Butene
ORGANIC CHEMISTRY Chapter 8 8.9B Reactions of other Carbenes Dihalocarbenes(二氯卡宾) OH CHC CCh CCb H Cl C CI CH H t CCl CH2C-C、H H CH C\CH3 H CH3 CH H (CH3)3COK CHCl3 Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 8 8.9B Reactions of Other Carbenes: Dihalocarbenes (二氯卡宾) CHCl3 OH − CCl2 Cl −H+ Cl − CCl2 CH3 C H C H CH3 CCl + 2 CH3 C H C H CH3 C Cl Cl H C CH3 C CH3 H C Cl Cl + + CHCl3 (CH3)3COK Cl Cl