Studies on the Mechanism, Selectivity, and Synthetic Utility of Lactone Reduction Using SmI<sub>2</sub> and H<sub>2</sub>O
作者:Dixit Parmar、Lorna A. Duffy、Dhandapani V. Sadasivam、Hiroshi Matsubara、Paul A. Bradley、Robert A. Flowers、David J. Procter
DOI:10.1021/ja906396u
日期:2009.10.28
esters and lactones have long been thought to lie outside the reducing range of SmI(2), activation of the lanthanide reagent by H(2)O allows some of these substrates to be manipulated in an unprecedented fashion. For example, the SmI(2)-H(2)O reducing system shows complete selectivity for the reduction of 6-membered lactones over other classes of lactones and esters. The kinetics of reduction has been
A Ring Size-Selective Reduction of Lactones Using SmI<sub>2</sub> and H<sub>2</sub>O
作者:Lorna A. Duffy、Hiroshi Matsubara、David J. Procter
DOI:10.1021/ja078137d
日期:2008.1.30
The Sml(2)-H2O reducing systems shows complete selectivity for six-membered lactones over other classes of lactone and esters. Experimental and computational studies suggest that the origin of the selectivity lies in the initial electron-transfer to the lactone carbonyl.
Stereocontrolled total synthesis of (±)-ptaquilosin, the aglycone of ptaquiloside, a bracken carcinogen
Starting from α-allyl-δ-valerolactone, stereocontrolled synthesis of ptaquilosin (2), the aglycone of a brackencarcinogenptaquiloside (1) has been achieved in racemic form, which includes a novel deformylation-hydroxylation reaction (21 → 23) as one of the key steps.