A Novel, General Method for the Synthesis of Nitrile Oxides: Dehydration of <i>O</i>-Silylated Hydroxamic Acids
作者:Dieter Muri、Jeffrey W. Bode、Erick M. Carreira
DOI:10.1021/ol991396q
日期:2000.2.1
O-Silylated hydroxamicacids serve as stable, readily accessible, crystalline precursors to nitrile oxides when treated with trifluoromethanesulfonic anhydride and triethylamine. Under these mild conditions in the presence of olefins O-silylated hydroxamicacids afford isoxazoline cycloadducts. This procedure represents a novel, general method for the one-step generation of nitrile oxides, which complements
condensation with carbonyl compounds, alkylation, and oxidation with oxygen to provide 3,5-disubstituted 2-isoxazolines as useful synthetic building blocks. Raney nickel hydrogenolysis of 3-[(diethoxyphosphoryl)methyl]-2-isoxazolines gives β-hydroxy-β′-phosphoryl ketones bearing a variety of functional groups, which can be further converted into α,β-unsaturated β′-phosphoryl ketones.
SYNTHESIS OF A NEW PHOSPHORUS-FUNCTIONALIZED NITRILE OXIDE, α-(DIETHYLPHOSPHONO)ACETONITRILE OXIDE, AND CYCLOADDITION LEADING TO 3-(DIETHYLPHOSPHONOMETHYL)-Δ<sup>2</sup>-ISOXAZOLINES
作者:Otohiko Tsuge、Shuji Kanemasa、Hiroyuki Suga
DOI:10.1246/cl.1986.183
日期:1986.2.5
Cycloaddition of α-(diethylphosphono)acetonitrile oxide, a new phosphorus-functionalized nitrile oxide, leads to 3-phosphonomethyl-Δ2-isoxazolines which are useful as Δ2-isoxazoline unit-introducing reagents.