pyridinium chloride
{{Short description|Chemical compound}}
{{Chembox
| Name =
| Reference = {{Cite web |url=https://www.chemicalbook.com/ProductMSDSDetailCB0725473_EN.htm |title=Pyridine hydrochloride(628-13-7) MSDS Melting Point Boiling Point Density Storage Transport |publisher=ChemicalBook |access-date=2019-03-22}}{{Cite encyclopedia |last=Wilson |first=Michael W. |chapter=Pyridinium Chloride |year=2001 |publisher=John Wiley & Sons |language=en |doi=10.1002/047084289x.rp287m |isbn=9780470842898 |title=Encyclopedia of Reagents for Organic Synthesis }}
| IUPACName = Pyridinium chloride
| ImageFile = Pyridiniumchlorid.svg
| ImageFile1 = Pyridinium-chloride-3D-balls.png
| ImageSize = 120px
| ImageCaption = The chemical structure of pyridinium chloride
| ImageName = Pyridinium chloride
| OtherNames = Pyridine hydrochloride
| SystematicName =
| Section1 = {{Chembox Identifiers
| CASNo = 628-13-7
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 1U87419851
| EC_number = 211-027-4
| InChI = AOJFQRQNPXYVLM-UHFFFAOYSA-N
| PubChem = 69401
| SMILES = C1=CC=[NH+]C=C1.[Cl-]
}}
| Section2 = {{Chembox Properties
| Formula = C5H6NCl
| Appearance = Hygroscopic white crystals
| Density = 1.34 g/cm3
| LogP =
| MolarMass = 115.56 g/mol
| MeltingPtC = 144
| BoilingPt = Decomposes
| pKa = 5
| Solubility = 85 g / 100 mL
| SolubleOther = Soluble in chloroform, ethanol, insoluble in diethyl ether
| VaporPressure = 1 (0 °C)
}}
| Section3 = {{Chembox Structure
| Coordination =
| CrystalStruct =
| MolShape =
}}
| Section4 =
| Section5 =
| Section6 =
| Section7 = {{Chembox Hazards
| MainHazards = Irritant
| AutoignitionPt = Non-flammable
| FlashPt = Non-flammable
| NFPA-H = 2
| NFPA-F = 0
| NFPA-R = 0
| NFPA-S =
| ExternalSDS = [https://www.fishersci.com/shop/msdsproxy?storeId=10652&productName=AC222281000]
| GHSPictograms = {{GHS07}}
| GHSSignalWord = Warning
| HPhrases = {{H-phrases|302|312|315|319|332|335}}
| PPhrases = {{P-phrases|261|264|270|271|280|301+312|302+352|304+312|304+340|305+351+338|312|321|330|332+313|337+313|362|403+233|405|501}}
| LD50 = 1600 mg/kg (oral, rat)
}}
}}
Pyridinium chloride is an organic chemical compound with a formula of C5H5NHCl.
Preparation
Pyridinium chloride can be produced by passing hydrogen chloride in pyridine dissolved in diethyl ether. The chemical formula is as follows:
:{{chem2 | C5H5N + HCl -> C5H6N+Cl- ↓ }}
Acidity
Containing a pyridinium ion, pyridinium chloride has a pKa of approximately 5, slightly more acidic than that of typical amines. This is due to the hybridization of the nitrogen: the nitrogen is sp2 hybridized and more electronegative than those nitrogens in ammonium cations, which are sp3 hybridized. Hence they are stronger acids than amines and can be more easily deprotonated by bases.{{Cite web|url=https://www.brainyresort.com/en/pyridine-synthesis-and-reactivity/|title=Pyridine: synthesis and reactivity {{!}} BrainyResort|date=2016-11-08|website=Brainy Resort|language=en-GB|access-date=2019-03-28}}