Rh-Catalyzed Coupling of Acrylic/Benzoic Acids with α-Diazocarbonyl Compounds: An Alternative Route for α-Pyrones and Isocoumarins

2022 ◽  
Author(s):  
Chao Hong ◽  
Shuling Yu ◽  
Zhanxiang Liu ◽  
Yuhong Zhang
Keyword(s):  
Benzoic Acids ◽  
Alternative Route

Exploring the Diversity of Religion

2010 ◽  
Vol 4 (1) ◽  
pp. 46-66
Author(s):  
Arkotong Longkumer
Keyword(s):  
Cultural Identity ◽  
Nation Building ◽  
Religious Movement ◽  
The Political ◽  
Alternative Route ◽  
British Colonialism ◽  
The North

This article considers the importance of “religion” and “identity” in the process of fieldwork in the North Cachar Hills, Assam, India. The political sensitivities in the region provided a difficult context in which to do fieldwork. This is chiefly because of the various armed insurrections, which have arisen as a consequence of the complicated remnants of British colonialism (1834–1947), and the subsequent post-independence challenge of nation building in India. This article raises important methodological questions concerning fieldwork and the relational grounding of the fieldworker relative to the inside/outside positions. It reflects on these issues by discussing the Heraka, a Zeme Naga religious movement. Their ambiguity and “in-between” character accommodates both the “neo-Hindu” version of a nation or Hindutva (Hinduness) and the larger Naga (primarily Christian) assertion of their own cultural and religious autonomy. The Heraka provides an alternative route into ideas of nationhood, religious belonging and cultural identity.

Substituted N,N-Dimethyl-3-(phenylthio)- and -4-(phenylthio)benzylamines

1992 ◽  
Vol 57 (1) ◽  
pp. 194-203 ◽  
Author(s):  
Karel Šindelář ◽  
Vojtěch Kmoníček ◽  
Marta Hrubantová ◽  
Zdeněk Polívka
Keyword(s):  
Serotonin Receptors ◽  
Hydrobromic Acid ◽  
Antidepressant Activity ◽  
Benzoic Acids ◽  
Lithium Aluminium Hydride ◽  
Acid Chlorides ◽  
Activity Inhibition ◽  
Lithium Aluminium ◽  
The Brain

(Arylthio)benzoic acids IIa - IIe and VIb - VId were transformed via the acid chlorides to the N,N-dimethylamides which were reduced either with diborane "in situ" or with lithium aluminium hydride to N,N-dimethyl-(arylthio)benzylamines Ia - Ie and Vb - Vd. Leuckart reaction of the aldehydes IX and X with dimethylformamide and formic acid afforded directly the amines Va and Ve. Demethylation of the methoxy compounds Ia and Ve with hydrobromic acid resulted in the phenolic amines If and Vf. The most interesting N,N-dimethyl-4-(phenylthio)benzylamine (Va) hydrochloride showed affinity to cholinergic and 5-HT2 serotonin receptors in the rat brain and some properties considered indicative of antidepressant activity (inhibition of serotonin re-uptake in the brain and potentiation of yohimbine toxicity in mice).

Kinetics and Mechanism of Decomposition of 1,3-Bis(4-methylphenyl)triazene Catalyzed with Substituted Benzoic Acids in 25% Aqueous Methanol-General or Specific Catalysis?

1994 ◽  
Vol 59 (9) ◽  
pp. 2029-2041
Author(s):  
Oldřich Pytela ◽  
Taťjana Nevěčná
Keyword(s):  
Benzoic Acids ◽  
Hammett Equation ◽  
Aqueous Methanol ◽  
Mechanism Of Decomposition ◽  
Kinetics Of Decomposition ◽  
Independent Variable ◽  
Amino Derivatives ◽  
Substituted Benzoic Acids ◽  
The Individual ◽  
Kinetics Of

The kinetics of decomposition of 1,3-bis(4-methylphenyl)triazene catalyzed with 13 substituted benzoic acids of various concentrations have been measured in 25 vol.% aqueous methanol at 25.0 °C. The rate constants observed (297 data) have be used as values of independent variable in a series of models of the catalyzed decomposition. For the catalytic particles were considered the undissociated acid, its conjugated base, and the proton in both the specific and general catalyses. Some models presumed formation of reactive or nonreactive complexes of the individual reactants. The substituent effect is described by the Hammett equation. The statistically best model in which the observed rate constant is a superposition of a term describing the dependence on proton concentration and a term describing the dependence on the product of concentrations of proton and conjugated base is valid with the presumption of complete proton transfer from the catalyst acid to substrate, which has been proved. The behaviour of 4-dimethylamino, 4-amino, and 3-amino derivatives is anomalous (lower catalytic activity as compared with benzoic acid). This supports the presumed participation of conjugated base in the title process.

Kinetic study of hydrolysis of benzoates. part xxvii. ortho substituent effect in alkaline hydrolysis of phenyl esters of substituted benzoic acids in aqueous Bu4NBr

2009 ◽  
Vol 74 (1) ◽  
pp. 29-42 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Signe Vahur ◽  
Oksana Travnikova ◽  
Ilmar A. Koppel
Keyword(s):  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Pure Water ◽  
Substituent Effects ◽  
Benzoic Acids ◽  
Resonance Effects ◽  
The Media ◽  
Substituted Benzoic Acids ◽  
Hydrolysis Of ◽  
Ortho Substituent

The second-order rate constants k (in dm3 mol–1 s–1) for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5, have been measured spectrophotometrically in aqueous 0.5 and 2.25 M Bu4NBr at 25 °C. The substituent effects for para and meta derivatives were described using the Hammett relationship. For the ortho derivatives the Charton equation was used. For ortho-substituted esters two steric scales were involved: the EsB and the Charton steric (υ) constants. When going from pure water to aqueous 0.5 and 2.25 M Bu4NBr, the meta and para polar effects, the ortho inductive and resonance effects in alkaline hydrolysis of phenyl esters of substituted benzoic acids, became stronger nearly to the same extent as found for alkaline hydrolysis of C6H5CO2C6H4-X. The steric term of ortho-substituted esters was almost independent of the media considered. The rate constants of alkaline hydrolysis of ortho-, meta- and para-substituted phenyl benzoates (X-C6H4CO2C6H5, C6H5CO2C6H4-X) and alkyl benzoates, C6H5CO2R, in water, 0.5 and 2.25 M Bu4NBr were correlated with the corresponding IR stretching frequencies of carbonyl group, (ΔνCO)X.

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