On the formation of pyridine in the interstellar medium

Nitrogen-substituted polycyclic aromatic hydrocarbons (NPAHs) have been proposed to play a key role in the astrochemical evolution of the interstellar medium, but the formation mechanism of even their simplest building block - the aromatic pyridine molecule - has remained elusive for decades. Here w...

Full description

Saved in:
Bibliographic Details
Published in:Physical chemistry chemical physics : PCCP 2015-01, Vol.17 (47), p.32000-32008
Main Authors: Parker, Dorian S N, Kaiser, Ralf I, Kostko, Oleg, Troy, Tyler P, Ahmed, Musahid, Sun, Bing-Jian, Chen, Shih-Hua, Chang, A H H
Format: Article
Language:English
Subjects:
Asymptotic properties
Derivatives
Formations
High temperature environments
INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Interstellar matter
Pyridines
Synthesis (chemistry)
Vitamins
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nitrogen-substituted polycyclic aromatic hydrocarbons (NPAHs) have been proposed to play a key role in the astrochemical evolution of the interstellar medium, but the formation mechanism of even their simplest building block - the aromatic pyridine molecule - has remained elusive for decades. Here we reveal a potential pathway to a facile pyridine (C5H5N) synthesis via the reaction of the cyano vinyl (C2H2CN) radical with vinyl cyanide (C2H3CN) in high temperature environments simulating conditions in carbon-rich circumstellar envelopes of Asymptotic Giant Branch (AGB) stars like IRC+10216. Since this reaction is barrier-less, pyridine can also be synthesized via this bimolecular reaction in cold molecular clouds such as in TMC-1. The synchronized aromatization of precursors readily available in the interstellar medium leading to nitrogen incorporation into the aromatic rings would open up a novel route to pyridine derivatives such as vitamin B3 and pyrimidine bases as detected in carbonaceous chondrites like Murchison.
ISSN:1463-9076
1463-9084
DOI:10.1039/c5cp02960k