The Brønsted acid-catalyzed
synthesis of secondary amides
from ketones under mild conditions is described via transoximation
and Beckmann rearrangement using O-protected oximes as more stable
equivalents of explosive O-protected hydroxylamines. This methodology
could be applied to highly rearrangement-selective amide synthesis
from α-branched alkyl aryl ketones and performed on a 1-g scale.
The presence of water is essential for this reaction, and its role
was clarified by isotope-labeling experiments.
The Brønsted acid-catalyzed synthesis of nitriles is described via transoximation under mild conditions using an O-protected oxime as a more stable equivalent of explosive O-protected hydroxylamines. The nitrile was generated via an O-protected aldoxime produced from the aldehyde and an O-protected oxime through transoximation. The reaction could be performed on a 1 g scale.
Inspired by bio-synthesis, we demonstrate Brønsted acid catalyzed transoximation for the synthesis of oximes without using hydroxylamine salts in water.
The
Brønsted acid-catalyzed synthesis of primary amines from acetyl
arenes and alkanes with C –C bond cleavage is described. Although
the conversion from an acetyl group to amine has traditionally required
multiple steps, the method described herein, which uses an oxime reagent
as an amino group source, achieves the transformation directly via
domino transoximation/Beckmann rearrangement/Pinner reaction. The
method was also applied to the synthesis of γ-aminobutyric acids,
such as baclophen and rolipram.
Nanoimprint lithography (NIL) has received attention as alternative lithographic technology, which can fabricate fine patterns of semiconductor devices at low cost. Application of NIL may lead to the reduction of number of process steps and cost of manufacturing of dual-damascene structure, by simultaneous fabrication of holes and trenches. Therefore, in this study, we investigated fabrication of dual-damascene structure using NIL and dry-etching. However, the difficulty in dry-etching process is high as the holes and trenches are etched together using single resist mask. Suppression of defects during the NIL process and the suppression of resist consumption and CD shift during the etching process, is critical. To address these issues, we used a high etching resistance resist, optimized the NIL process to reduce defects, and optimized the template structure and etching process to suppress resist consumption and CD shift. As a result, a dual-damascene structure with L/S = 4X/4X nm was obtained.
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