Rotational Study of cis- and trans-Acrylic Acid–Trifluoroacetic Acid

2013 ◽  
Vol 117 (50) ◽  
pp. 13500-13503 ◽  
Author(s):  
Qian Gou ◽  
Gang Feng ◽  
Luca Evangelisti ◽  
Walther Caminati
Keyword(s):  
Acrylic Acid ◽  
Trifluoroacetic Acid ◽  
Cis And Trans

Aliphatic diazo compounds. X. The reaction of α-diazoacetophenone with methanolic sodium methoxide

1977 ◽  
Vol 55 (1) ◽  
pp. 145-152 ◽  
Author(s):  
Peter Yates ◽  
R. J. Mayfield
Keyword(s):  
Acrylic Acid ◽  
Benzoic Acid ◽  
Sodium Methoxide ◽  
Methyl Benzoate ◽  
Diazo Compounds ◽  
Dilute Solution ◽  
Cis And Trans

The reaction of α-diazoacetophenone (1) with methanolic sodium methoxide in dilute solution gives 3-benzoyl-5-hydroxy-4-phenylpyrazole (4), 3-benzoyl-4-hydroxy-5-phenyl-pyrazole (5), 3-benzoyl-5-methoxy-4-phenylpyrazole (9), 3-benzoyl-4-phenylpyrazole (6), 5-benzoyltetrazole (7), 3,6-dibenzoyldihydro-s-tetrazine (10), cis- and trans- β-benzoyl- α-phenyl-acrylic acid, acetophenone, methyl benzoate, and benzoic acid. The pyrazoles 4, 5, and 9 are considered to arise via reaction of 1 to give α-methoxyacetophenone followed by further reaction of the anion of the latter with 1. Evidence in accord with this view was obtained by a study of the products formed when 1 was treated with methanolic sodium methoxide in the presence of 2-methoxy-4′-methylacetophenone. Acetophenone is considered to arise by reduction of 1 via phenylglyoxal 2-monohydrazone (37); condensation of 1 with the enolate ion derived from acetophenone then can give the pyrazole 6, while condensation of 1 with 37 could give the tetrazole 7.

Ipso nitration. XVIII. Nitrationof 2-chloro-1,3,5-trimethylbenzene: nitration ipso to chlorine

1978 ◽  
Vol 56 (10) ◽  
pp. 1348-1357 ◽  
Author(s):  
Alfred Fischer ◽  
Sachdev Singh Seyan
Keyword(s):  
Acetic Acid ◽  
Ambient Temperature ◽  
Trifluoroacetic Acid ◽  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
Trifluoroacetic Anhydride ◽  
Trans Isomers ◽  
Dimethyl Benzyl ◽  
Cis And Trans Isomers ◽  
Cis And Trans

Nitration of 2-chloro-1,3,5-trimethylbenzene in acetic anhydride gives the cis and trans isomers of 4-chloro-1,3,5-trimethyl-4-nitrocyclohexa-2,5-dienyl acetate (1, 21%), the cis and trans isomers of 3-chloro-2,4,6-trimethyl-4-nitrocyclohexa-2,5-dienyl acetate (2, 6%), and 2-chloro-1,3,5-trimethyl-4-nitrobenzene (73%). Diene 1 reacts with acidified aqueous acetone to form the corresponding dienol, acidified methanol to form the methyl ether, and hydrogen chloride to form the corresponding chloride. In acetic acid a mixture of 4-chloro-3,5-dimethyl-benzyl derivatives and 3-chloro-2,4,6-trimethylphenyl acetate are formed. In trifluoroacetic acid – trifluoroacetic anhydride and also in boron trifluoride etherate, 2-chloro-1,3,5-trimethyl-4-nitrobenzene is the predominant product. Diene 2 on reaction with acetic acid, acidified methanol, trifluoroacetic acid – trifluoroacetic anhydride, and boron trifluoride etherate gives 3-chloro-2,4,6-trimethylphenyl acetate. Some 2-chloro-4-nitromesitylene is obtained in trifluoromethanesulfonic acid. Diene 2 also gives the acetate on standing at ambient temperature or at −20 °C, and on pyrolysis. Diene 1 gives 4-chloro-3,5-dimethylphenylnitromethane on standing at ambient temperature or at −20 °C but a mixture of 2-chloro-1,3,5-trimethyl-4-nitrobenzene, chloromesitylene, and 3-chloro-2,4,6-trimethylphenyl acetate on pyrolysis.

Total synthesis of ylango sesquiterpenoids: (+)-cis- and (+)-trans-sativenediol, (+)-helminthosporal, (+)-helminthosporol, prehelminthosporal, prehelminthosporal diethyl acetal, (+)-victoxinine, (+)-isosativenediol

1977 ◽  
Vol 55 (6) ◽  
pp. 1039-1044 ◽  
Author(s):  
Edward Piers ◽  
Hans-Peter Isenring
Keyword(s):  
Total Synthesis ◽  
Trifluoroacetic Acid ◽  
Chromium Trioxide ◽  
Major Product ◽  
Hydroxy Ketone ◽  
Diethyl Acetal ◽  
Total Syntheses ◽  
Tricyclic Ketone ◽  
Cis And Trans ◽  
Synthetic Transformations

Oxidation of the previously prepared olefinic alcohol 26 with chromium trioxide – pyridine in dichloromethane containing trifluoroacetic acid gave the tricyclic ketone 29 as the major product. Hydroxylation of the latter, followed by reduction of the resulting α-hydroxy ketone 31, afforded a 1:1 mixture of (+)-cis- (22) and (+)-trans-sativenediol (23). In view of earlier synthetic transformations reported by a number of different researchers, the present work also constitutes formal total syntheses of the enantiomers of the following sesquiterpenoids: (−)-helminthosporal (1), (−)-helminthosporol (2), prehelminthosporal (3), prehelminthosporal diethyl acetal (4), (−)-victoxinine (8), and (−)-isosativenediol (19).

Flavan derivatives. XXIV. cis- and trans-3-Methoxyflavanones

1968 ◽  
Vol 21 (12) ◽  
pp. 3015 ◽  
Author(s):  
JW Clark-Lewis ◽  
RW Jemison ◽  
V Nair
Keyword(s):  
Hydrogen Bonding ◽  
Manganese Dioxide ◽  
Trifluoroacetic Acid ◽  
Trans Configuration ◽  
Trans Isomers ◽  
Cis And Trans ◽  
Cis Isomer

Oxidation of three 2,3-cia-3,4-cis-3-methoxyflavan-4-ols with active manganese dioxide gave the corresponding 2,3-cis-3-methoxyflavanones which were equilibrated in deuterochloroform containing trifluoroacetic acid to mixtures of cis- (c.33%) and trans-3-methoxyflavanones (c.67%). Tominaga's base-catalysed cyclization of 2'-hydroxy-α-methoxycha1cones to 3-methoxyflavanones has been found to yield the 2,3-trans isomers. The higher stability of the 2,3-trans-configuration of 3-hydroxy- flavanones (dihydroflavonols) compared with 3-methoxyflavanones is attributed to hydrogen bonding; no cis-isomer was detected when acid-catalysed epimerization of a trans-3-hydroxyflavanone was attempted. M.m.r. data are reported for the compounds described.

Soft ionic liquid based resistive memory characteristics in a two terminal discrete polydimethylsiloxane cylindrical microchannel

2020 ◽  
Vol 8 (38) ◽  
pp. 13368-13374
Author(s):  
Muhammad Umair Khan ◽  
Gul Hassan ◽  
Jinho Bae
Keyword(s):  
Ionic Liquid ◽  
Acrylic Acid ◽  
Sodium Hydroxide ◽  
Sodium Salt ◽  
Resistive Memory ◽  
Cylindrical Microchannel ◽  
Memory Characteristics ◽  
Poly Acrylic Acid

This paper proposes a novel soft ionic liquid (IL) electrically functional device that displays resistive memory characteristics using poly(acrylic acid) partial sodium salt (PAA-Na+:H2O) solution gel and sodium hydroxide (NaOH) in a thin polydimethylsiloxane (PDMS) cylindrical microchannel.

Trypanocidal Structure-Activity Relationshipfor Cis- and Trans-methylpluviatolide

Planta Medica ◽  
2008 ◽  
Vol 74 (03) ◽  
Author(s):  
R Silva ◽  
J Saraiva ◽  
S Albuquerque ◽  
C Curti ◽  
PM Donate ◽  
...  
Keyword(s):  
Structure Activity ◽  
Cis And Trans

The Role of the Initiator System in the Synthesis of Acidic Multifunctional Nanoparticles Designed for Molecular Imprinting of Proteins

2020 ◽  
Vol 65 (1) ◽  
pp. 28-41
Author(s):  
Marwa Aly Ahmed ◽  
Júlia Erdőssy ◽  
Viola Horváth
Keyword(s):  
Acrylic Acid ◽  
Binding Affinity ◽  
Molecular Imprinting ◽  
Low Temperatures ◽  
Ammonium Persulfate ◽  
Sodium Bisulfite ◽  
Multifunctional Nanoparticles ◽  
High Affinity ◽  
Initiator System

Multifunctional nanoparticles have been shown earlier to bind certain proteins with high affinity and the binding affinity could be enhanced by molecular imprinting of the target protein. In this work different initiator systems were used and compared during the synthesis of poly (N-isopropylacrylamide-co-acrylic acid-co-N-tert-butylacrylamide) nanoparticles with respect to their future applicability in molecular imprinting of lysozyme. The decomposition of ammonium persulfate initiator was initiated either thermally at 60 °C or by using redox activators, namely tetramethylethylenediamine or sodium bisulfite at low temperatures. Morphology differences in the resulting nanoparticles have been revealed using scanning electron microscopy and dynamic light scattering. During polymerization the conversion of each monomer was followed in time. Striking differences were demonstrated in the incorporation rate of acrylic acid between the tetramethylethylenediamine catalyzed initiation and the other systems. This led to a completely different nanoparticle microstructure the consequence of which was the distinctly lower lysozyme binding affinity. On the contrary, the use of sodium bisulfite activation resulted in similar nanoparticle structural homogeneity and protein binding affinity as the thermal initiation.

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