Hydrophobically Directed Selective Reduction of Ketones
作者:Mark R. Biscoe、Ronald Breslow
DOI:10.1021/ja0379924
日期:2003.10.1
extreme case, there was a 40-fold selectivity reversal. Lithiumborohydride showed no such change in selectivity and favored acetyl reduction in both solvents. Salt and cosolvent effects indicate that hydrophobic packing is involved in the reaction of hydrophobic reagents with the aryl ketones. Some special interaction of the pentafluorophenyl group with aryl rings was also detected.
Requirements for Selective Hydrophobic Acceleration in the Reduction of Ketones
作者:Mark R. Biscoe、Christopher Uyeda、Ronald Breslow
DOI:10.1021/ol0481481
日期:2004.11.1
Reductions of various quaternized hydrophobic beta-keto amines were performed in water and in methanol using borohydride anions carrying hydrophobic groups. The most important requirement of the substrate to permit hydrophobically accelerated selective reductions is the ability of the hydrophobic group of the substrate and its attached keto group to attain a coplanar relationship. Some derivatives of naturally occurring steroid diones have also been employed as substrates to probe the mechanism and utility of these hydrophobically accelerated selective reductions further.
β-NAPHTHYL DERIVATIVES OF ETHANOLAMINE AND N-SUBSTITUTED ETHANOLAMINES
作者:TONY IMMEDIATA、ALLAN R. DAY
DOI:10.1021/jo01211a005
日期:1940.9
Asymmetric synthesis of β-dialkylamino alcohols by transfer hydrogenation of α-dialkylamino ketones
Transfer hydrogenation of representative aryl and heteroaryl dialkylaminomethyl ketones with formic acid-triethylamine, catalyzed by RuCl[(R,R)-TsDPEN](eta-p-cymene), produces the corresponding beta-dialkylamino alcohols, 97-99% ee, in 50-73% yields. Asymmetric synthesis of (R)-macromerine, 98% ee, the cactus Coryphantha macromeris alkaloid, is also described. (C) 2009 Elsevier Ltd. All rights reserved.
Kosmalski, Tomasz, Acta poloniae pharmaceutica, 2010, vol. 67, # 6, p. 717 - 721