Carbon-carbon double bond functional groups are often protected through a popular bromination/debromination method because of their reactivity. An ultrasonic-enhanced stereoselective debromination of vic-dibromides wi...Carbon-carbon double bond functional groups are often protected through a popular bromination/debromination method because of their reactivity. An ultrasonic-enhanced stereoselective debromination of vic-dibromides with metallic zinc powder in aqueous media has been developed, which generates E-alkenes with excellent yields. The reactivity of vic-dibromides decreases in the order of 1,2-dibromo-1,2-diphenylethane>1,2-dibromo-1-phenylethane>1,2-dibromo-1,2-dialkylethane.展开更多
The ? ?vicinal dibromo carboxylic acid and its derivatives were debrominated with Sm/HOAc system to afford the corresponding cinnamic acid and its derivatives in good yields under mild conditions.
The debromination of diphenyl bromomethane (Ph_2CHBr) using polymers with viologen structure as electron--transfer catalyst (ETC) afforded tetraphenylethane in good yields under het- erophase conditions.
The active intermediate'carbon radical' was detected by the spin—trapping reagent (POBN) during the debromination of Ph_2CHBr in the presence of viologen derivatives as electron—transfer catalysts(ETC).
In the presence of equimolar triethylamine,vicinal dibromides were found to be easily debrominated by dibutyl telluride,forming the co- rresponding olefins.
基金Supported by the National Natural Science Foundation of China(No.2 0 372 0 2 4 2 0 172 0 18) +2 种基金the Excellent ScientistFoundation of Anhui ProvinceChina(No.2 0 0 10 4 0 ) the Natural Science Foundation of the Educational Departm entof AnhuiProvince
文摘Carbon-carbon double bond functional groups are often protected through a popular bromination/debromination method because of their reactivity. An ultrasonic-enhanced stereoselective debromination of vic-dibromides with metallic zinc powder in aqueous media has been developed, which generates E-alkenes with excellent yields. The reactivity of vic-dibromides decreases in the order of 1,2-dibromo-1,2-diphenylethane>1,2-dibromo-1-phenylethane>1,2-dibromo-1,2-dialkylethane.
基金Project supported by the National Natural Science Foundation of China(No.29872010)the Natural Science Foundation of Zhejiang Province(No.298067)
文摘The ? ?vicinal dibromo carboxylic acid and its derivatives were debrominated with Sm/HOAc system to afford the corresponding cinnamic acid and its derivatives in good yields under mild conditions.
文摘The debromination of diphenyl bromomethane (Ph_2CHBr) using polymers with viologen structure as electron--transfer catalyst (ETC) afforded tetraphenylethane in good yields under het- erophase conditions.
文摘The active intermediate'carbon radical' was detected by the spin—trapping reagent (POBN) during the debromination of Ph_2CHBr in the presence of viologen derivatives as electron—transfer catalysts(ETC).
文摘In the presence of equimolar triethylamine,vicinal dibromides were found to be easily debrominated by dibutyl telluride,forming the co- rresponding olefins.
