scholarly journals Negative-type Chemically Amplified Photosensitive Semi-alicyclic Polybenzoxazole via Acid-catalyzed Electrophilic Substitution

2005 ◽  
Vol 37 (2) ◽  
pp. 74-81 ◽  
Author(s):  
Ken-ichi Fukukawa ◽  
Yuji Shibasaki ◽  
Mitsuru Ueda
Keyword(s):  
Electrophilic Substitution ◽  
Negative Type ◽  
Chemically Amplified ◽  
Acid Catalyzed

scholarly journals Negative-type Chemically Amplified Photosensitive Novolac

2008 ◽  
Vol 21 (1) ◽  
pp. 161-164 ◽  
Author(s):  
Yuta Saito ◽  
katsuhisa Mizoguchi ◽  
Mitsuru Ueda
Keyword(s):  
Negative Type ◽  
Chemically Amplified

Nucleophilic Cyclization/Electrophilic Substitution of (2,2-Dialkoxyethyl)ureas: Highly Regioselective Access to Novel 4-(Het)arylimidazolidinones and Benzo[d][1,3]diazepinones

Synthesis ◽  
2020 ◽  
Vol 52 (21) ◽  
pp. 3263-3271
Author(s):  
Andrey V. Smolobochkin ◽  
Almir S. Gazizov ◽  
Nazerke K. Otegen ◽  
Julia K. Voronina ◽  
Anna G. Strelnik ◽  
...  
Keyword(s):  
Substitution Reaction ◽  
Electrophilic Substitution ◽  
Biologically Active ◽  
Electrophilic Substitution Reaction ◽  
Reaction Sequence ◽  
Active Compounds ◽  
Acid Catalyzed ◽  
High Yields ◽  
Nucleophilic Cyclization ◽  
Mechanism Of The Reaction

Imidazolidin-2-one and 1,3-benzodiazepin-2-one scaffolds are structural motifs of many biologically active compounds. Herein, we report a highly regioselective acid-catalyzed intramolecular nucleophilic cyclization/intermolecular electrophilic substitution reaction sequence of (2,2-dialkoxyethyl)ureas. The reaction benefits from readily available starting materials, a simple workup procedure, moderate to high yields of target compounds, and provides a convenient entry to previously unknown 4-(het)arylimidazolidinones and 5-(het)arylbenzodiazepinones. The proposed mechanism of the reaction is also discussed.

Chemically amplified negative resists using acid-catalyzed etherification of carbinol

1992 ◽  
Vol 18 (4) ◽  
pp. 341-351 ◽  
Author(s):  
Shou-ichi Uchino ◽  
Midori Katoh ◽  
Toshio Sakamizu ◽  
Michiaki Hashimoto
Keyword(s):  
Chemically Amplified ◽  
Acid Catalyzed

What’s in a name? The MacDonald condensation

2016 ◽  
Vol 20 (08n11) ◽  
pp. 855-888 ◽  
Author(s):  
Timothy D. Lash
Keyword(s):  
Total Synthesis ◽  
Electrophilic Substitution ◽  
Historical Review ◽  
Dicarboxylic Acids ◽  
Type Systems ◽  
Air Oxidation ◽  
Bond Forming ◽  
Expanded Porphyrins ◽  
Acid Catalyzed ◽  
Porphyrin Synthesis

In 1960, MacDonald and coworkers introduced a new method for porphyrin synthesis that involved the acid-catalyzed condensation of dipyrrylmethane dialdehydes with [Formula: see text],[Formula: see text]-diunsubstituted dipyrrylmethanes or the related dicarboxylic acids, followed by an air oxidation. The key bond forming steps entail electrophilic substitution at two pyrrole units with the aldehyde moieties to generate, following elimination of water, a 5,15-dihydroporphyrin or porphodimethene intermediate. Following addition of sodium acetate, or in later procedures zinc acetate, the dihydroporphyrins readily air oxidize to the fully aromatic porphyrin system. This strategy, which parallels chemistry contemporaneously developed by R. B. Woodward at Harvard for the total synthesis of chlorophyll [Formula: see text], demonstrated that dipyrrylmethanes were sufficiently stable to be utilized as intermediates in porphyrin syntheses and that porphodimethene formation circumvented acidolytic scrambling reactions that might lead to isomeric porphyrin products. This type of chemistry was later adapted by Johnson, Woodward and others to prepare porphyrin-type systems by a “3 + 1” strategy, or expanded porphyrins by “3 + 2” or other combinations of oligopyrrolic precursors. In recent years, the term “MacDonald condensation” has been increasingly used to describe other types of chemistry involving oligopyrrolic intermediates. Following on from a historical review of this area, guidelines for the identification of MacDonald-type reactions are proposed.

Dry lithography of chemically amplified acid-catalyzed deep-UV and e-beam resist

1993 ◽  
Author(s):  
Yosef Y. Shacham-Diamand ◽  
Clency Lee-Yow ◽  
Jean M. J. Frechet ◽  
S. Ming Lee
Keyword(s):  
Chemically Amplified ◽  
Acid Catalyzed ◽  
Deep Uv
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