2-chloropyridine

Structural formula
General
Surname	2-chloropyridine
other names	o -chloropyridine ortho -chloropyridine
Molecular formula	C 5 H 4 ClN
Brief description	colorless liquid with a pyridine-like odor
External identifiers / databases
CAS number 109-09-1 EC number 203-646-3 ECHA InfoCard 100.003.316 PubChem 7977 Wikidata Q209364
properties
Molar mass	113.55 g mol −1
Physical state	liquid
density	1.21 g cm −3 (20 ° C)
Melting point	−46 ° C
boiling point	170 ° C
Vapor pressure	2.2 h Pa (20 ° C) 15 hPa (50 ° C) 25 hPa (65 ° C)
solubility	poor in water (27 g l −1 at 20 ° C)
Refractive index	1.5320 (20 ° C)
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 302-310 + 330-315-318-373-410 P: 260-280-302 + 352 + 310-304 + 340 + 310-305 + 351 + 338 + 310-403 + 233
Toxicological data	80 mg kg −1 ( LD 50 ,  rat ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

2-chloropyridine is an organic compound that belongs to the heterocycles (more precisely: heteroaromatics ). It consists of a pyridine ring which is substituted in the 2-position with chlorine . The compound is isomeric to 3-chloropyridine and 4-chloropyridine .

presentation

In general, common electrophilic aromatic substitutions on pyridine are not possible or only possible with poor yield. Furthermore, pyridine would preferentially be substituted in the 3-position and 2-chloropyridine would only arise as a by-product. However, 2-chloropyridine can be prepared by reacting with molecular chlorine in the presence of catalytic amounts of palladium (II) chloride .

properties

2-Chloropyridine forms flammable vapor-air mixtures above the flash point of 64 ° C. The ignition temperature is 585 ° C. The substance therefore falls into temperature class T1.

use

4-Azaphenothiazine is an important intermediate for the synthesis of active substances and can be produced from 2-chloropyridine and 2-aminothiophenol .

By lithiation , 2-chloropyridine can be converted into an organolithium compound , which serves as a starting compound for other pyridine derivatives that are not directly accessible.

Individual evidence

1. ↑ ^{a b c d e f g h i j k} Entry on 2-chloropyridine in the GESTIS substance database of the IFA , accessed on January 9, 2019(JavaScript required) .
2. ↑ ^{a b} David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-112.
3. ↑ Data sheet 2-chloropyridine (PDF) from Merck , accessed on March 20, 2011.
4. ↑ JA Joules, K. Mills: Heterocyclic Chemistry . 4th edition, Blackwell Science, Oxford 2000, ISBN 0-632-05453-0 , pp. 77-81.
5. Jump up ↑ Bernhard Kutscher, Hans Reinhold Dieter, Hans-Günther Trömer, Beate Bartz, Jürgen Engel, Axel Kleemann: New synthesis of 4-azaphenothiazine . In: Liebig's annals . tape 1995 , no. 3 , 1995, p. 591-592 , doi : 10.1002 / jlac.199519950381 .
6. ↑ JA Joules, K. Mills: Heterocyclic Chemistry . 5th edition, Blackwell Publishing, Chichester 2010, ISBN 978-1-4051-9365-8 , pp. 125-141.