ORGANIC CHEMISTRY Chapter 16 16.11 The Addition of Organometallic Reagents: The Reformatsky reaction Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 16.11 The Addition of Organometallic Reagents: The Reformatsky Reaction
ORGANIC CHEMISTRY Chapter 16 (1)Et2O (CH3h2CH--C-CH(CH32 CH3 CH2MgBr (2)H3O O CH3)2CH-C-CH(CH3)280% CH2CH If a chiral atom attached to the carbonyl group the stereoselectivity of nucleophilic addition follows the Cram's rule CH3CH CH3-C—C H R Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 (CH3)2CH C CH(CH3)2 O + CH3CH2MgBr (1) Et2O (2) H3O+ (CH3)2CH C CH(CH3)2 OH CH2CH3 80% If a chiral atom attached to the carbonyl group, the stereoselectivity of nucleophilic addition follows the Cram’s rule. C O R C H CH3 CH3CH2
ORGANIC CHEMISTRY Chapter 16 Cram’ s rule Nu. RL R Nu R R Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 Cram’s rule M L S O R S L M O R Nu S L M O R S L M O R Nu
ORGANIC CHEMISTRY Chapter 16 Ph H Et() CH3Mgx H Et (2)HO H O HPh Et CH OH H Et HO→H major H CH Et HO CH H Et H Ph H-oh minor H Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 Ph H Et C H O H Ph Et O H (2) H3O+ (1) CH3MgX H Ph Et OH H CH3 H Ph Et HO H CH3 Ph H Et H OH CH3 Ph H Et HO H CH3 major minor
ORGANIC CHEMISTRY Chapter 16 Reformasky reaction Bruno Zn C=0+ Br-C-CO,R -C-C-COR enzene a-Bromo ester OH H2O C-C-CO2R B-Hydroxy ester OH OH COR (1OH, H2O C-C-COH (2)H Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 Reformasky Reaction C O + Br C CO2R Zn benzene C C CO2R BrZnO H3O+ C C CO2R OH β−Hydroxy ester α−Bromo ester (1) OH, H2O (2) H+ C C CO2H OH C C CO2R OH