Chemical properties of ylidene derivatives of azines. 4. Structures of the products of protonation and transformation of dihydroazinylidenecyanoacetic esters in concentrated sulfuric acid

1990 ◽  
Vol 26 (7) ◽  
pp. 801-807
Author(s):  
I. V. Oleinik ◽  
O. A. Zagulyaeva ◽  
A. Yu. Denisov ◽  
V. P. Mamaev
Keyword(s):  
Sulfuric Acid ◽  
Chemical Properties ◽  
Concentrated Sulfuric Acid ◽  
Derivatives Of

Synthèse de quelques dérivés du tétrahydro-4,5,6,7 benzothiazoline-Δ2α-acétate d'éthyle

1968 ◽  
Vol 46 (23) ◽  
pp. 3643-3648 ◽  
Author(s):  
Réal Laliberté ◽  
Hilda Warwick ◽  
Georges Médawar
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Spectroscopic Evidence ◽  
Concentrated Sulfuric Acid ◽  
Derivatives Of

Some derivatives of α-cyano tétrahydro benzothiazoline-Δ2α-acetic acid and their intermediates are described. The lack of reactivity of this class of compounds and products of treatment with concentrated sulfuric acid have been studied. Assignment of configuration was based on infrared and ultraviolet spectroscopic evidence.

The Phthalimidomethyl Rearrangement

1990 ◽  
Vol 43 (11) ◽  
pp. 1817 ◽  
Author(s):  
JFK Wilshire
Keyword(s):  
Sulfuric Acid ◽  
Nitrogen Atom ◽  
Carbon Atom ◽  
Acid Solution ◽  
Sulfuric Acid Solution ◽  
Hindered Rotation ◽  
Initial Location ◽  
Concentrated Sulfuric Acid ◽  
Derivatives Of

The discovery of a new acid-catalysed monodentate N → C aromatic rearrangement, namely the phthalimidomethyl rearrangement, is reported. In this rearrangement, discovered during the reaction of N-hydroxymethylphthalimide with certain alkyl N-(4-nitrophenyl)carbamates in concentrated sulfuric acid solution, the phthalimidomethyl group migrates from its initial location on the nitrogen atom of the carbamate function to a carbon atom of the nitrophenyl group. Evidence, provided by an appropriate 'crossover' experiment, indicates that the rearrangement is intermolecular. Hindered rotation about the N(carbamoyl)-aryl bond of the N-phthalimidomethyl derivatives of both ethyl and methyl N-(2,4-dinitrophenyl)carbamate is reported.

Gallium Arsenide Integrated Circuits Decapsulation Technique Using Mixed Acid Chemistry For Die-Level Failure Analysis

2018 ◽  
Author(s):  
Harold Jeffrey M. Consigo ◽  
Ricardo S. Calanog ◽  
Melissa O. Caseria
Keyword(s):  
Gallium Arsenide ◽  
Sulfuric Acid ◽  
Nitric Acid ◽  
Integrated Circuits ◽  
Failure Analysis ◽  
Mixed Acid ◽  
Optimum Parameters ◽  
Plastic Package ◽  
Fuming Nitric Acid ◽  
Concentrated Sulfuric Acid

Abstract Gallium Arsenide (GaAs) integrated circuits have become popular these days with superior speed/power products that permit the development of systems that otherwise would have made it impossible or impractical to construct using silicon semiconductors. However, failure analysis remains to be very challenging as GaAs material is easily dissolved when it is reacted with fuming nitric acid used during standard decapsulation process. By utilizing enhanced chemical decapsulation technique with mixture of fuming nitric acid and concentrated sulfuric acid at a low temperature backed with statistical analysis, successful plastic package decapsulation happens to be reproducible mainly for die level failure analysis purposes. The paper aims to develop a chemical decapsulation process with optimum parameters needed to successfully decapsulate plastic molded GaAs integrated circuits for die level failure analysis.

PRODUCTION OF SULFOCATIONITE BY MODIFICATION OF NATURAL COAL WITH CONCENTRATED SULFURIC ACID

2020 ◽  
Vol 3 (441) ◽  
pp. 104-109
Author(s):  
N.A. Bektenov ◽  
◽  
N.C. Murzakassymova ◽  
M.A. Gavrilenko ◽  
А.N. Nurlybayeva ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Concentrated Sulfuric Acid ◽  
Natural Coal

Addition of primary alcohols to 3-chlorononafluoro-1,5-hexadiene and perfluoro-1,3,5-hexatriene

1985 ◽  
Vol 50 (8) ◽  
pp. 1714-1726 ◽  
Author(s):  
Václav Dědek ◽  
Igor Linhart ◽  
Milan Kováč
Keyword(s):  
Sulfuric Acid ◽  
Primary Alcohols ◽  
Principal Product ◽  
Allyl Rearrangement ◽  
Concentrated Sulfuric Acid ◽  
Sodium Alkoxide

Sodium alkoxide-catalyzed addition of methanol, ethanol and propanol to 3-chlorononafluoro-1,5-hexadiene (I) proceeds at temperatures -35 °C to 8 °C with allyl rearrangement, affording 1,6-dialkoxy-1,1,2,3,4,4,5,6,6-octafluoro-2,4-hexadiene (V) as the principal product, along with 1,6-dialkoxy-1,2,3,3,4,5,6,6-octafluoro-1,5-diene (VI) and trans-1,6-dialkoxy-1,1,2,3,4,4,5,6,6-nonafluoro-2-hexene (VII). The ethers Va-Vc consist of the cis,trans- and trans,trans-isomers in about 3 : 1 ratio, whereas the ethers VIa-VIc have trans,trans-configuration. Ethers Vc and VIc react with concentrated sulfuric acid to give dipropyl 2,3,4,5-tetrafluoro-2,4-hexadienedioate (IX) and dipropyl 2,3,4,4,5-pentafluoro-2-hexenedioate (X), respectively, whereas the ether VIIc affords a mixture of propyl 6-propyloxy-2,3,4,4,5,6-heptafluoro-2-hexenoate (XI) and ester X. Addition of methanol to perfluoro-1,3,5-hexatriene (II) affords 1,1,2,3,4,5,6,6-octafluoro-1,6-dimethoxy-3-hexene (XIII) as the principal product.

scholarly journals 4,5,6-Trichloropyrimidine-2-carboxamide

Molbank ◽  
10.3390/m1190 ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. M1190
Author(s):  
Andreas S. Kalogirou ◽  
Panayiotis A. Koutentis
Keyword(s):  
Sulfuric Acid ◽  
Elemental Analysis ◽  
Maldi Tof ◽  
Concentrated Sulfuric Acid

Reaction of 4,5,6-trichloropyrimidine-2-carbonitrile (1) with concentrated sulfuric acid at ca. 20 °C gave 4,5,6-trichloropyrimidine-2-carboxamide (5) in 91% yield. The new compound was fully characterized by IR, MALDI-TOF, NMR and elemental analysis.

Charge-discharge cyclability of ultracapacitor with glass wool separator under high concentrated sulfuric acid

2016 ◽  
Author(s):  
Mohd Ferdaus Mohd Yaacob ◽  
Zulkarnain Ahmad Noorden ◽  
Jasrul Jamani Jamian
Keyword(s):  
Sulfuric Acid ◽  
Glass Wool ◽  
Concentrated Sulfuric Acid ◽  
Charge Discharge

Regioselective Bromination of Anilines in the Presence of Nitrosonium Hydrogensulfate in Concentrated Sulfuric Acid

1995 ◽  
Vol 5 (2) ◽  
pp. 65-66 ◽  
Author(s):  
Mikhail V. Gorelik ◽  
Vera I. Lomzakova ◽  
Elena A. Khamidova ◽  
Vitalii Ya. Shteiman ◽  
Marianna G. Kuznetsova ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Concentrated Sulfuric Acid

High-Temperature Raman Investigation of Concentrated Sulfuric Acid Mixtures:  Measurement of H-Bond ΔHValues between H3O+or H5O2+and HSO4-

2002 ◽  
Vol 106 (43) ◽  
pp. 10162-10173 ◽  
Author(s):  
G. E. Walrafen ◽  
W.-H. Yang ◽  
Y. C. Chu
Keyword(s):  
Sulfuric Acid ◽  
High Temperature ◽  
Concentrated Sulfuric Acid
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