Stereoselective Synthesis of (−)-(1<i>R</i>,1′<i>R</i>,5′<i>R</i>,7′<i>R</i>)-1-Hydroxy-<i>exo</i>-brevicomin and (+)-<i>exo</i>-Brevicomin from 3,4,6-Tri-<i>O</i>-acetyl-<scp>D</scp>-glucal
Stereoselective syntheses of (−)‐(1R,1′R,5′R,7′R)‐1‐hydroxy‐exo‐brevicomin (1) and (+)‐exo‐brevicomin (2) were accomplished from 3,4,6‐tri‐O‐acetyl‐D‐glucal (5; Schemes 2 and 3). Chemoselective reduction, Grignard reaction, BartonMcCombie deoxygenation, and ketalization were used as key steps.
Pheromone Synthesis, CLXXXII. Synthesis of (1R,1′R,5′R,7′R)- and (1S,1′R,5′R,7′R)- 1-hydroxy-exo-Brevicomin, the Components of the Male-Produced Volatiles of the Mountain Pine Beetle,dendroctonus ponderosae
作者:Yūsuke Yokoyama、Kenji Mori
DOI:10.1002/jlac.199719970509
日期:1997.5
Both (1R)- and (1S)-hydroxy derivatives of (+)-exo-brevicomin (1R,1′R,5′R,7′R)-1-(5′-methyl-6′,8′-dioxabicyclo[3.2.1]-octyl)ethanol (1) and its (1S)-isomer (2)} were synthesized by employing Sharpless asymmetric dihydroxylation as the key reaction.
Highly α-Selective Hydrolysis of α,β-Epoxyalcohols using Tetrabutylammonium Fluoride
作者:Purba Mukerjee、Mohammed Abid、Frank C. Schroeder
DOI:10.1021/ol1015306
日期:2010.9.17
We report a simple method for the highly regio- and stereoselective hydrolysis of alpha,beta-epoxyalcohols. Treatment of enantiopure epoxyalcohols derived from Sharpless epoxidation with TBAF/H(2)O resulted in exclusive ring opening at the normally disfavored alpha-position, providing access to arabino- or lyxo-configured triols with full preservation of stereochemical purity. The method was applied in syntheses of 5-deoxy-L-arabinose (26) and a family of bicyclic acetals based on the insect pheromone hydroxybrevicomin (4).