Photochemical behaviour of α-diketones on a silica gel surface: a novel photoreaction by intramolecular trapping of an excited ketone carbonyl oxygen by an aryl group

1997 ◽  
pp. 1271-1274 ◽  
Author(s):  
Tadashi Hasegawa ◽  
Manabu Imada ◽  
Yoshihiro Imase ◽  
Yuko Yamazaki ◽  
Michikazu Yoshioka
Keyword(s):  
Silica Gel ◽  
Carbonyl Oxygen ◽  
Aryl Group ◽  
Ketone Carbonyl ◽  
Photochemical Behaviour

THE CONDENSATION OF CERTAIN γ-KETONIC ESTERS WITH AROMATIC ALDEHYDES

1932 ◽  
Vol 6 (6) ◽  
pp. 605-613 ◽  
Author(s):  
C. F. H. Allen ◽  
G. F. Frame
Keyword(s):  
Carbonyl Group ◽  
Aromatic Aldehydes ◽  
Sodium Methylate ◽  
Ring Closure ◽  
Aryl Group ◽  
Appropriate Treatment ◽  
Ketone Carbonyl ◽  
Branched Chain ◽  
Cyclic Compounds ◽  
Chloride Methyl

The condensation of methyl and ethyl α-phenyl-β-(para-substituted)benzoyl propionates with benzaldehyde and piperonal in the presence of sodium methylate, followed by acidification, has been found to produce cyclic compounds; the latter are shown to be lactols, six of which are described. The spontaneous ring closure is probably due to the highly branched chain. A mechanism for the reaction is proposed.On oxidation with chromic acid, α-diketones are formed; the latter contain the aryl group introduced as aldehyde. The lactols resemble triphenylcarbinol in several respects, forming a chloride, methyl ether, and acetate on appropriate treatment, all of which, on hydrolysis, regenerate the lactol. They also give colored solutions with concentrated sulphuric acid, from which the starting material is recovered on addition to water. From this work it is evident that in arylated γ-ketonic esters the hydrogen atom alpha to the ketone carbonyl group is more active in alkaline aldol condensations than the hydrogen in the alpha position to the carbalkoxy carbonyl group; the observation of others, that the conjugated system [Formula: see text] is more stable than [Formula: see text], has been confirmed.

Segmental motion of alkyl chains grafted on silica gel, studied by neutron scattering

1983 ◽  
Vol 44 (4) ◽  
pp. 497-503 ◽  
Author(s):  
J.P. Beaufils ◽  
M. C. Hennion ◽  
R. Rosset
Keyword(s):  
Neutron Scattering ◽  
Silica Gel ◽  
Segmental Motion ◽  
Alkyl Chains

Preparation and Characterization of Biodiesel from Karanja Oil by Using Silica Gel Reactor

2014 ◽  
Author(s):  
Sukanta Mondal ◽  
Kaniz Ferdous ◽  
M. Rakib Uddin ◽  
Maksudur R. Khan ◽  
M. A. Islam ◽  
...  
Keyword(s):  
Silica Gel ◽  
Karanja Oil

Detection of a covalent-ionic carbinolamine intermediate in aqueous media by SDTLC on silica gel plates

2007 ◽  
Vol 20 (3) ◽  
pp. 227-230 ◽  
Author(s):  
Ana Reverdito ◽  
Mariano García ◽  
Alejandra Salerno ◽  
Oscar Locani ◽  
Isabel Perillo
Keyword(s):  
Silica Gel ◽  
Aqueous Media

Synthesis Process and Structure of Al/Mg Modified Silica-gel Particle.

2000 ◽  
Vol 116 (1) ◽  
pp. 56-61
Author(s):  
Tatsuo YAMAGUCHI ◽  
Toshiaki NAKAI ◽  
Kunihiko TAKEDA
Keyword(s):  
Silica Gel ◽  
Synthesis Process ◽  
Modified Silica ◽  
Modified Silica Gel

Exploration of Bis(Arylimidazole) Iridium Picolinate Complexes

2017 ◽  
Author(s):  
Aron Huckaba ◽  
sadig aghazada ◽  
iwan zimmermann ◽  
giulia grancini ◽  
natalia gasilova ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Photophysical Properties ◽  
Structure Property ◽  
Aryl Group ◽  
Ligand Modification ◽  
Property Relationship ◽  
Structure Property Relationship

The straightforward synthesis and photophysical properties of a new series of heteroleptic Iridium (III) bis(2-arylimidazole) picolinate complexes is reported. Each complex has been characterized by NMR, UV-Vis, cyclic voltammetry, and the emissive properties of each is described. By systematically modifying first the cyclometallating aryl group on the arylimidazole ligand and then the picolinate ligand, the ramifications of ligand modification in these complexes was better understood through the construction of a structure-property relationship.

Exploration of Bis(Arylimidazole) Iridium Picolinate Complexes

2017 ◽  
Author(s):  
Aron Huckaba ◽  
sadig aghazada ◽  
iwan zimmermann ◽  
giulia grancini ◽  
natalia gasilova ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Photophysical Properties ◽  
Structure Property ◽  
Aryl Group ◽  
Ligand Modification ◽  
Property Relationship ◽  
Structure Property Relationship

The straightforward synthesis and photophysical properties of a new series of heteroleptic Iridium (III) bis(2-arylimidazole) picolinate complexes is reported. Each complex has been characterized by NMR, UV-Vis, cyclic voltammetry, and the emissive properties of each is described. By systematically modifying first the cyclometallating aryl group on the arylimidazole ligand and then the picolinate ligand, the ramifications of ligand modification in these complexes was better understood through the construction of a structure-property relationship.

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