Sarah Siska. C. A. Morales Models for Carbonyl Addition Introduction Chem 206 ■ Definition of terms Fischer, and the Dawn of Asymmetric Induction Felkin product commonly COOH COOH accepted term for the major Nu carbonyl addition product predicted 1)HCN the felkin-Anh model also predicted by Cram and Karabatsos R M for steric cases. Cornforth for CH2OH a-heteroatom(non-chelating)cases M arabinose L-gluconic acid RuX not isolated initially. but later found in mother liquor Felkin-Anh model "To my knowledge these observations furnish the first definitive evidence that further synthesis with asymmetric Felkin products anti-Felkin products/ systems proceeds in an asymmetric manner Emil Fischer. 1894 Fischer. E. Ber. 1890. 23 2611 NUM Fischer. E. Ber. 1894. 27. 3189 R RS Assimilation in nature: propagation of asymmetry from one chiral molecule to another CO. HcO glucose also Cram-chelate produc Fischer. E. Ber. 1894. 27. 3189 Freudenberg, K Adv in Carbohydrate Chem. 1966, 21, 1Sarah Siska, C. A. Morales Models for Carbonyl Addition Introduction Chem 206 R RS RM RL O H RL RM O H RM/L O X R RS RM RL HO Nu Nu RL OH RM Nu RM/L OH X Nu RL OH RM Nu RM/L OH X R RS RM RL Nu OH RL/X RS RM R O M Felkin product = commonly accepted term for the major carbonyl addition product predicted by the Felkin-Anh model; also predicted by Cram and Karabatsos for steric cases, Cornforth for a-heteroatom (non-chelating) cases Nu: Felkin-Anh model Felkin products anti-Felkin products ■ Examples: also Cram-chelate product Nu–M Nu–M Nu–M + + + ■ Definition of Terms glucose* CHO H OH HO H HO H CH2OH CO2, H2CO H OH H OH HO H HO H CH2OH COOH H OH HO H HO H CH2OH HO H COOH chlorophyll* Fischer, E. Ber. 1894, 27, 3189 Freudenberg, K. Adv. in Carbohydrate Chem. 1966, 21, 1 chlorophyll* Fischer, and the Dawn of Asymmetric Induction Fischer, E. Ber. 1890, 23, 2611 Fischer, E. Ber. 1894, 27, 3189 Assimilation in nature: propagation of asymmetry from one chiral molecule to another "To my knowledge these observations furnish the first definitive evidence that further synthesis with asymmetric systems proceeds in an asymmetric manner." L-arabinose 1) HCN 2) hydrolysis L-mannonic acid L-gluconic acid + ~3 : 1 not isolated initially, but later found in mother liquor -Emil Fischer, 1894