ORGANIC CHEMISTRY Chapter 16 16.9 The Addition of Hydrogen Cyanide Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 16.9 The Addition of Hydrogen Cyanide
ORGANIC CHEMISTRY Chapter 16 OH R OH C=o +HCN S CH CH 3 cN Cyanohydrin (H) (H) -羟基腈 R、OHH2O R、OH-H2O R CHo=C-COH CH 3 CN H or Oh CH3 CO,H a-Hydroxy acid a, B-Unsaturated acid α-羟基酸 ,-不饱和酸 Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 R C CH3 O + HCN R C CH3 OH CN α−羟基腈 OH (H) (H) Cyanohydrin H+ or OH − R C CH3 OH CO2H R CH2 C CO2H H2O α−羟基酸 α,β−不饱和酸 H2O α−Hydroxy acid α,β−Unsaturated acid R C CH3 OH CN
ORGANIC CHEMISTRY Chapter 16 16.10 The Addition of ylides The Witti g Reaction Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 16.10 The Addition of Ylides: The Wittig Reaction
ORGANIC CHEMISTRY Chapter 16 CH2 +CH2=P(C6H5)3 Phosphorus ylide 叶立德 Wittig reaction BuL CH3I +(C6H5)3P-CH3-P(C6H5)3 + CH2-P(C6H4 CH2-P(C6H5)3 Phosphorus ylide叶立德( Wittig reagent) Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 CH2 P(C6H5) + 3 O CH2 Phosphorus ylide 叶立德 Wittig reaction CH3I + (C6H5)3P CH3 P(C6H5)3 CH2 P(C6H5)3 CH2 P(C6H5)3 (Wittig reagent) BuLi Phosphorus ylide 叶立德
ORGANIC CHEMISTRY Chapter 16 Mechanism O P(C6H5)3 THE C/+ R2C-P(C6H5) C—C R R AP(C6H5)3 R R C=C、+O=P(C6H5) R R Department of Chemistry, Xiamen University
ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 16 Mechanism Mechanism C + O R2C P(C6H5)3 C O C R R P(C6H5)3 C O C R R P(C6H5)3 C C R R + P(C6H5) O 3 THF
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