scholarly journals Photoinduced intramolecular charge-transfer reactions in 4-amino-3-methyl benzoic acid methyl ester: A fluorescence study in condensed-phase and jet-cooled molecular beams

2007 ◽  
Vol 119 (2) ◽  
pp. 195-204 ◽  
Author(s):  
Amrita Chakraborty ◽  
Samiran Kar ◽  
D N Nath ◽  
Nikhil Guchhait
Keyword(s):  
Charge Transfer ◽  
Methyl Ester ◽  
Benzoic Acid ◽  
Intramolecular Charge Transfer ◽  
Acid Methyl Ester ◽  
Molecular Beams ◽  
Transfer Reactions ◽  
Fluorescence Study ◽  
Acid Methyl ◽  
Charge Transfer Reactions

Derivate des Benzo[1.3]dioxols, 431 Über Benzo [1.3] dioxolcarbonsäuren / Derivatives of 1,3-Benzodioxoles, 43 1,3-Benzodioxolecarboxylic Acids

1978 ◽  
Vol 33 (7-8) ◽  
pp. 465-471
Author(s):  
Franz Daliacker ◽  
Volker Mues ◽  
In-O Kim
Keyword(s):  
Carboxylic Acid ◽  
Methyl Ester ◽  
Benzoic Acid ◽  
Myristic Acid ◽  
Good Yield ◽  
Acid Ester ◽  
Acid Methyl Ester ◽  
Acid Methyl ◽  
Derivatives Of

Abstract We describe the possibilities of formation and preparation of the “natural” 1,3-benzodioxolecarboxylic acids 1, 2, 4, 6 b, and 7, already mentioned in literature. Myristic acid (3e) was prepared in good yield from 3-methoxy-4,5-dihydroxy-benzoic acid ester (3c) , which could be easily made from 3-methoxy-2,3-carbonyldioxy-benzoic acid methylester (3b). Myristicic acid methylester (3d) could be subjected to methylation and hydrolysis leading to 3e without any difficulties. 4.6-dimethoxy-1,3-benzodioxole-5-carboxylic acid (5b) was prepared in good yields by oxidation of 4,6-dimethoxy-1,3-benzodioxole-5-aldehyde (5a). 5.7-dimethoxy-1,3-benzodioxole-carboxylic acid (13f), one of the “unnatural” 1,3-benzodioxolecarboxylic acids, derivatives of o-ipiperonylic acid (8), was prepared from 5-amino-7-methoxy-1,3- benzodioxole-4carboxylic acid methyl ester (13b) by diazotisation, elimination of nitrogen, methylation, and hydrolysis. A comparison of our measured pkA-values showed the strongest acidity belonging to 5,6-dimethoxy-1,3-benzodioxole-4-carbocylic acid (11).

Structure and degree of charge transfer of two polymorphs of a 1:1 molecular complex: [2,2′-bis-1,3-dithiole][9-dicyanomethylene-4,5,7-trinitrofluorene-2-carboxylic acid methyl ester] (TTF-MeDC2TNF)

2003 ◽  
Vol 59 (4) ◽  
pp. 505-511 ◽  
Author(s):  
Amparo Salmerón-Valverde ◽  
Sylvain Bernès ◽  
Juan Gerardo Robles-Martínez
Keyword(s):  
Charge Transfer ◽  
Carboxylic Acid ◽  
Methyl Ester ◽  
Acid Methyl Ester ◽  
Structural Features ◽  
Space Group ◽  
Acid Methyl ◽  
Organic Complexes ◽  
Crystal Packings ◽  
Degree Of Charge Transfer

A new organic charge-transfer complex, C18H7N5O8·C6H4S4, has been prepared using TTF (tetrathiafulvalene) as a donor (D) and MeDC2TNF (9-dicyanomethylene-4,5,7-trinitro-fluorene-2-carboxylic acid methyl ester) as an acceptor (A). Two monoclinic polymorphs of the 1:1 salt were crystallized and characterized by X-ray diffraction. Form α crystallizes in space group P21/n with Z′ = 1, while form β crystallizes in space group C2/c with Z′ = 1\over 2 and the MeDC2TNF moiety disordered across a twofold axis. Both phases have mixed-stack crystal packings, which are characteristic of semiconducting one-dimensional organic complexes. However, the observed crystal packings are significantly different, with a single D...A interlayer separation of 3.452 Å for the disordered β polymorph and interlayer separations of 3.378 and 3.483 Å in the case of the ordered α form. These variations are reflected in the degree of charge transfer, δ, which was estimated on the basis of the b 2u stretching-mode frequency shift observed in the IR spectra for the cyano groups of the MeDC2TNF radical anion. The fact that the charge transfer is more efficient for α-(TTF-MeDC2TNF) than for β-(TTF-MeDC2TNF) (δ = 0.35 and 0.31, respectively) is consistent with the structural features observed for each crystalline form.

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