Selective deprotection of esters using magnesium and methanol
作者:Yao-Chang Xu、Elaine Lebeau、Clint Walker
DOI:10.1016/s0040-4039(00)73392-2
日期:1994.8
The use of magnesium metal in methanol for the deprotection of alkyl esters is described. This mild reagent also provides good to excellent selectivity to cleave different esters. The order of the reactivity of this reagent towards acyl cleavages was found to be: p-nitrobenzoate > acetate > benzoate > pivaloate > trifluroacetamide.
A process which can afford a large quantity of the title compound was explored by modifying the Horton’s original route. The developed process features highly stereoselective reduction of the oxime with sodium dihydrobis(2-methoxyethanolato)aluminate(1-) and efficient dehydrobromination with 1,8-diazabicyclo[5.4.0]undec-7-ene.