Abstract
Preparation of pentachloropyridine is carried out by chlorination of pyridine ring or it is obtained from perchlorocyclopentene-3-one via several steps. Perchloropyridines are mainly involved in nucleophilic reactions and produce various substituted perchloropyridines, whereas the nature of solvent and nucleophile hindrance affect the regiochemistry of the reactions. Furthermore, these compounds participated in cross-coupling reactions and produced arylated and alkenylpyridines pyridines. Additionally, they are involved in photochemical reactions and produce ring-fused systems. Oxidation of pentachloropyridine gave pentachloropyridine-Noxide, which is active toward nucleophiles at ortho positions. The reaction of perchloropyridines with methyl fluorosulphonate produced corresponding Nmethylated compounds, which are active toward nucleophilic attack. Organometallic compounds obtained from pentachloropyridined in reaction with various electrophiles produced corresponding substituted products.
Keywords: Biological Activities, Heteronium Salts, N-ethylpentachloropyri-dinium Fluoroborate, Nucleophilic Substitution Reactions, Pentaalkynylpyridines, Pentachloropyridine, Pentachloropyridine-N-oxide, Sonogashira Cross-Coupling, Steric Hindrance, Suzuki–Miyaura Cross-Coupling, Tetraalkenylpyridines, Tetraalkynylpyridines, Tetrachloro-4-pyridyl Copper, Tetrachloro-4-pyridyl-lithium, Tetrachloro-4-pyridylmagnesium Chloride, Tetrachloropyridines, Tetrahydro-5Hpyrido[ 3, 2-b]indoles, Tetrahydro-9H-pyridi[2, 3-b]indoles, Thiazolo[2, 3-b] quinazolines, Trichloro-thiazolo[3, 2-a]pyrimidines.