D. A Evans, N. Finney Hydrazone Transformations- 1 Chem 206 Hydrazone Anions: A useful Reversed Polarity Equivalent R Me?N 1.03:2DMs A-C(+) A-C(+) R=H or alkyl nBu0cuN界rbu,N Lassaletta. J-M. et al. Tet Lett. 1992. 33 3691 J E. Baldwin, et al. JcS Chem. Comm. 1983. 1040 HcHO Wolff-Kishner Reduction Procedures Pr 1. n-BuLi NaoCH2 CH2O (HOCH2CH2)20 HoP 2. H/H2O reflux and then heat to210℃c larton D. H. R, Ives, D. A J, and Thomas B. R. J. chem. Soc. 1955. 2056. 1. n-BuLi.-78°c OCH3 For particulary hindered ketones: anhydrous hydrazine or formation of hydrazone under acid catalysis(hydrazine hydrazine dihydrochloride), then basi er these forcing conditions, saponification, epimerization, and methyl ether A-C avage can occur Mechanism R2C=N-NH R2C=N-NH R2C--NNH hydrolysis Me RnR→、一B9H J E. Baldwin. et al. JCS Chem. Comm. 1984. 1095 A-C(- RO-HR2C N N H (RDS)* –N2 R2C H R2C H H tBu N N iPr H H A C(+) N N:– R H R O iPr HO Ph H THF R H N N:– R H i N Pr N tBu i N Pr N tBu LiO H Ph H PhCHO R H N N: R A C(–) tBu N N iPr H Me2N N CH2 A C(–) CH3CO2 Me Me Me O O R Me H H H R N R' O O CH2Cl2 Me H N NH tBu O Me OCH3 O OCH3 Me Me O O OCH3 Me Me N N H tBu O OCH3 Me Me N N tBu H H + , H2O A C(–) A C(+) R2C N NH2 R2C N NH A C(–) A C(–) OH OH RO–H RO–H Me2N N R NO2 R' H O R' NO2 R H H H Me R Me Me Me HO R2C N NH H RO A C(+) Hydrazone Transformations-1 Chem 206 Hydrazone Anions: A useful Reversed Polarity Equivalent ✔✔ (+) (–) (–) n-BuLi, 0°C 2. H+ /H2O 95% 1. n-BuLi J. E. Baldwin, et al. JCS Chem. Comm. 1983, 1040. 1. n-BuLi, -78°C J. E. Baldwin, et al. JCS Chem. Comm. 1984, 1095. 58% Lassaletta, J-M, et al.Tet. Lett. 1992, 33, 3691. (40-92%) R=alkyl or aryl R'=H or alkyl + 1. O3 ; 2. DMS For particulary hindered ketones: anhydrous hydrazine or formation of hydrazone under acid catalysis (hydrazine/hydrazine dihydrochloride), then basify. Under these forcing conditions, saponification, epimerization, and methyl ether cleavage can occur. Barton, D. H. R., Ives, D. A. J., and Thomas, B. R. J. Chem. Soc. 1955, 2056. N2H4, NaOCH2CH2OCH2CH2OH, (HOCH2CH2 )2O Wolff-Kishner Reduction Procedures reflux and then heat to 210°C + Mechanism D. A. Evans, N. Finney RT, ca. 24h hydrolysis