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European Journal of Applied Sciences – Vol. 10, No. 3
Publication Date: June 25, 2022
DOI:10.14738/aivp.103.12335. Nagieva, I. T., Ali-zade, N. I., & Nagiyev, T. M. (2022). Gas-Phase Oxidation of Piperidine by "Green Oxidants" H2O2 and N2O.
European Journal of Applied Sciences, 10(3). 201-208.
Services for Science and Education – United Kingdom
Gas-Phase Oxidation of Piperidine by "Green Oxidants" H2O2 and
N2O
Nagieva I. T.
Baku State University
Ali-zade N. I.
ANAS Institute of Catalysis and Inorganic
Chemistry named after acad. M. F. Nagiyev 113 H. Javid Ave
370143 Baku, Azerbaijan Republic
Nagiyev T. M.
ANAS Institute of Catalysis and Inorganic Chemistry
named after acad. M. F. Nagiyev 113 H. Javid Ave
370143 Baku, Azerbaijan Republic
Baku State University
ANNOTATION
Reactions of piperidine oxidation by hydrogen peroxide and nitrogen oxide (1)
were investigated experimentally in the gas phase and at atmospheric pressure
without the use of catalysts. The reaction site for selective oxidation of piperidine
by hydrogen peroxide and nitric oxide (1) was identified, and consequently, optimal
conditions for obtaining pyridine and 2,3,4,5-tetrahydropyridine from piperidine
were revealed. Effect of the process parameters on reaction determinants in
coherently synchronized reactions of piperidine dehydrogenation and
decomposition of hydrogen peroxide and nitric oxide was demonstrated (1).
Keywords: hydrogen peroxide, nitric oxide (1), coherent synchronization of reactions,
"green oxidant", 2,3,4,5-tetrahydropyridine
Over the years, an interest in the chemistry of heterocyclic compounds has grown remarkably.
This is firstly due to the exceptional role that substances obtained on their basis play in
bioenergetics of an organism. Secondly, these are results of various types of physiological
activity. A large number of heterocyclic compounds are widely used in production of
pharmaceuticals. Development of fundamentally new methods for oxidation of pyridine bases
on the basis of cheap and accessible raw materials is one of the most important directions of
small chemistry. An increased interest in pyridine-based compounds is explained by the fact
that they are precursors of drugs with certain specific chemical properties. Therefore,
development of innovative technologies for selective use of practically important precursors
for pharmaceutical industry is relevant.
In this regard, fundamentally new reactions of piperidine oxidation by "green oxidants" H2O2
and N2O in the gas were investigated. It should be noted that the developed methodology of
hydrocarbon oxidation with the reaction of hydrogen peroxide decomposition [1-3] makes it
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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 3, June-2022
Services for Science and Education – United Kingdom
possible to obtain a number of important compounds, with relatively high yields and selectivity,
at atmospheric pressure, without the use of special catalysts. Property of hydrogen peroxide to
induce chemical reactions underlies these reactions. The key point is that hydrogen peroxide,
being decomposed into final products - water and oxygen, generates intermediate active
centers (•OH and HO•
2-radicals) into the system, which are selectively consumed in other
(target) reaction that does not proceed in the absence of the first. Later in [4], a concept was
put forward that made it possible to demonstrate a general provision on the interference in
chemical reactions. Using a determinant equation proposed by this concept, a quantitative
evaluation of the effect of primary reaction (decomposition of hydrogen peroxide) on
secondary - main reaction (oxidation of hydrocarbons) was conducted. A distinctive feature of
these reactions is that they proceed synchronously in a chemical system; they can be mutually
reinforced and weakened and are necessarily coherent in this state [1-4]. Experimental studies
on the oxidation of piperidine (PP) by hydrogen peroxide (Fig. 1) showed that (optimal
conditions for the process) when using 25 wt% concentration of hydrogen peroxide in an
aqueous solution, volume ratio PP: hydrogen peroxide = 1: 3, piperidine feed rate = 1.56 ml / h
and under temperature of 540°C, the maximum yield of pyridine is 65.2 wt%, with a selectivity
not lower than 98 wt% [5-9].
Furthermore, it follows from the results obtained that the process of oxidative dehydrogenation
of piperidine by the aqueous solution of hydrogen peroxide can be successfully used for similar
transformations in fragments of natural compounds. A reaction of piperidine dehydration to
pyridine was studied in a coherently synchronized mode.
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Nagieva, I. T., Ali-zade, N. I., & Nagiyev, T. M. (2022). Gas-Phase Oxidation of Piperidine by "Green Oxidants" H2O2 and N2O. European Journal of
Applied Sciences, 10(3). 201-208.
URL: http://dx.doi.org/10.14738/aivp.103.12335
Fig. 1. Effect of the temperature on the pyridine yield (1) and molecular oxygen (2). Feed rate
PP=1,56 ml/h, H2O2 concentration = 25 wt.%
Referring to these results, we attempted to quantify the inducing effect of the reaction of
hydrogen peroxide decomposition on the reaction of piperidine dehydrogenation.
Fig. 2. Effect of the temperature on the D value (1) and molecular oxygen (2). Feed rate PP=1,56
ml/h, H2O2 concentration = 25 wt.% volume ratio PP:H2O2 = 1:3