scholarly journals NMR Study on p-Substituted Derivatives of Benzoic Acid Methyl Ester

1967 ◽  
Vol 88 (1) ◽  
pp. 101-102
Author(s):  
Hisashi OKUDA ◽  
Makoto NAGAI
Keyword(s):  
Methyl Ester ◽  
Benzoic Acid ◽  
Acid Methyl Ester ◽  
Acid Methyl ◽  
Nmr Study ◽  
Derivatives Of

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).

Synthesis of 2-Cyanoethoxy and 2-(1H-Tetrazol-5-yl)ethoxy Derivatives of Glycyrrhetic Acid Methyl Ester

2018 ◽  
Vol 54 (12) ◽  
pp. 1868-1870
Author(s):  
A. D. Zorina ◽  
V. L. Polozova ◽  
S. A. Marchenko ◽  
S. I. Selivanov ◽  
R. E. Trifonov
Keyword(s):  
Methyl Ester ◽  
Acid Methyl Ester ◽  
Glycyrrhetic Acid ◽  
Acid Methyl ◽  
Derivatives Of

Mechanismen der elektronenstoßinduzierten Methanoleliminierung aus ortho- und para-substituierten Benzoesäuremethylestern / Mechanisms of Electron Impact Induced Elimination of Methanol from ortho- and para-Substituted Benzoic Acid Methyl Ester

1976 ◽  
Vol 31 (6) ◽  
pp. 870-875 ◽  
Author(s):  
Rupert Herrmann ◽  
Helmut Schwarz
Keyword(s):  
Mass Spectrometry ◽  
Methyl Ester ◽  
Benzoic Acid ◽  
Electron Impact ◽  
Acid Methyl Ester ◽  
Ring Expansion ◽  
Acid Methyl ◽  
Π Complex ◽  
Fragmentation Reactions ◽  
Ring Expansion Reaction

Using deuterium labelled compounds the mechanisms of methyl as well as methanol elimination from the title compounds have been established. It can be shown that in the case of 4-methoxy-methyl benzoic acid methyl ester the unusual methanol elimination from the [M-methyl]+ ion probably proceeds via the formation of a π-complex and a ring expansion reaction. In addition to this novel fragmentation some ortho-effects and other fragmentation reactions useful for an analytical identification of the ortho/para-isomers by means of mass spectrometry are discussed.

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