Isoquinoline
ISOQUINOLIN · LEUCOLINE · Benzopyridine · FEMA 2978 · 2-BENZAZINE · ISOQINOLINE · IsoquinoL · ISOCHINOLIN
Identifiers & Physical Properties
| CAS No. | 119-65-3 |
|---|---|
| Molecular formula | C9H7N |
| Average molar mass | 129.16 g/mol |
| Monoisotopic mass | 129.05784923 g/mol |
| SMILES | c1ccc2cnccc2c1 |
| InChIKey | AWJUIBRHMBBTKR-UHFFFAOYSA-N |
| PubChem CID | 8405 |
| ChEMBL | CHEMBL12315 |
| ChEBI | CHEBI:16092 |
| EC No. | 204-341-8 |
| DTXSID | DTXSID2047644 |
Chemical & Physical Properties
| XLogP | 2.1 |
|---|---|
| Topological polar surface area | 12.9 |
| Hydrogen bond donors | 0 |
| Hydrogen bond acceptors | 1 |
| Rotatable bonds | 0 |
| Heavy atoms | 10 |
| Formal charge | 0 |
| Complexity | 111 |
| LogP (partition coefficient) | 2.08 |
| LogS | -1.45 |
| Density | 1.097-1.1031.099 g/mL at 25 °C (lit.) |
| Solubility | 45204.52 mg/mL at 25 °CSlightly soluble in waterSoluble (in ethanol)5g/lpractically insoluble |
| Boiling point | 243.2242.00 to 243.00 °C. @ 760.00 mm Hg242-243 °C242-243 °C (lit.) |
| Melting point | 26.4725.5 - 26 °C26-28 °C (lit.) |
| Refractive index | 1.621-1.627n20/D 1.623(lit.) |
| Physical Description | LiquidLiquid or hygroscopic solid with a pungent odor like anise oil mixed with benzaldehydemp = 26.48 deg C[Merck Index] Light brownmp = 24-28 deg C[Acros Organics MSDS]Colourless liquid, hygroscopic platelets when solidHeavy-sweet balsamic, herbaceous aroma |
| Dissociation Constants | 5.42 (at 20 °C) |
| Kovats Retention Index | 1225.21251126912481272.91250.712401241.6213.1912551261126812651275.51261.2214212.1214.14214.68214.41214.09215.611934195819551980 |
| Collision Cross Section | 122.3 Ų [M+H]+ [CCS Type: DTBuffer gas: N2Ionization: APCI+Dataset: TOXCASTSource Identifier: DTXSID2047644] |
| Vapor pressure | 5Pa at 20℃ |
| FEMA | 2978 | ISOQUINOLINE |
| FLAVIS Number | 14.001 | Isoquinoline |
| Flash point | 225 °F |
| Storage conditions | 2-8°C |
| pKa (acidity coefficient) | 5.42(at 20℃) |
| Physical state | Low Melting Solid |
| Color | Light brown |
| pH | 7.5 (5g/l, H2O, 20℃) |
| Odor | at 0.10 % in triacetin. sweet balsam herbal benzaldehyde anise |
| Odor type | balsamic |
| Specific heat capacity | Cp(liquid): 1.52 J/(g·K), at 25℃ |
| JECFA Number | 1303 |
| Merck | 14,5222 |
| BRN | 107549 |
| Henry's law constant | 5.2×10-2 mol/(m3Pa) at 25℃, Mackay et al. (2006) |
| Dielectric constant | 10.7(20℃) |
| InChI | 1S/C9H7N/c1-2-4-9-7-10-6-5-8(9)3-1/h1-7H |
| InChIKey | AWJUIBRHMBBTKR-UHFFFAOYSA-N |
| SMILES | c1ccc2cnccc2c1 |
| LogP (partition coefficient) | 2.08 |
| Dissociation constant | 5.19 at 25℃ |
| Substances Added to Food (formerly EAFUS) | ISOQUINOLINE |
| FDA 21 CFR | 172.515 |
| CAS DataBase Reference | 119-65-3(CAS DataBase Reference) |
| EWG's Food Scores | 1 |
| FDA UNII | JGX76Y85M6 |
| NIST Chemistry Reference | Isoquinoline(119-65-3) |
| EPA Substance Registry System | Isoquinoline (119-65-3) |
| UNSPSC Code | 85151701 |
| NACRES | NA.24 |
| GHS pictogram | GHS06 |
| Signal word | Danger |
| GHS hazard statements | H302-H311-H315-H319-H412 |
| GHS precautionary statements | P264-P273-P280-P301+P312-P302+P352+P312-P305+P351+P338 |
| Personal protective equipment (PPE) | Eyeshields, Faceshields, Gloves, type P2 (EN 143) respirator cartridges |
| Hazard symbols | T |
| Risk statements (R) | 22-24-38-52/53-36/38-21/22-45 |
| Safety statements (S) | 36/37-45-36/37/39-61-53 |
| UN transport number | UN 2811 6.1/PG 3 |
| Water hazard class (WGK) | 2 |
| RTECS number | NW6825000 |
| TSCA inventory status | TSCA listed |
| Hazard class | 6.1Acute Tox. 3 DermalAcute Tox. 4 OralAquatic Chronic 3Eye Irrit. 2Skin Irrit. 2 |
| Packing group | II |
| Customs code | 29334900 |
| Storage class | 6.1C - Combustible acute toxic Cat.3toxic compounds or compounds which causing chronic effects |
| Toxicity | LD50 orally in rats: 360 mg/kg (Smyth) |
| REACH registrations | Active |
Safety & Regulations
| GHS classification | This chemical does not meet GHS hazard criteria for < 0.1% (1 of 1677) of reports.DangerH302 (> 99.9%): Harmful if swallowed [Warning Acute toxicity, oral]H311 (99.6%): Toxic in contact with skin [Danger Acute toxicity, dermal]H315 (93.4%): Causes skin irritation [Warning Skin corrosion/irritation]H319 (93.4%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]P262, P264, P264+P265, P270, P280, P301+P317, P302+P352, P305+P351+P338, P316, P321, P330, P332+P317, P337+P317, P361+P364, P362+P364, P405, and P501 (click each P-code to see the statement)Aggregated GHS information provided per 1677 reports by companies from 8 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.Reported as not meeting GHS hazard criteria per 1 of 1677 reports by companies.There are 7 notifications provided by 1676 of 1677 reports by companies with hazard statement code(s).Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. |
|---|---|
| Regulatory information | Chemical: IsoquinolineCommission Regulation (EC) No 1565/2000 (Repealed by Com. Implementing Reg. (EU) No 872/2012)Isoquinoline is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Isoquinoline are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)Status: Active Update: 07-01-2011 https://echa.europa.eu/registration-dossier/-/registered-dossier/5236Status: No longer Valid Update: 30-09-2010 https://echa.europa.eu/registration-dossier/-/registered-dossier/1356Isoquinoline: Does not have an individual approval but may be used under an appropriate group standard |
| Hazards summary | A moderate skin irritant[RTECS] Safe when used as a flavoring agent in food[JECFA] An irritantHighly toxic by skin absorptionHarmful by ingestion[Acros Organics MSDS] See Quinoline. |
| Hazard Classes and Categories | Acute Tox. 4 (> 99.9%)Acute Tox. 3 (99.6%)Skin Irrit. 2 (93.4%)Eye Irrit. 2 (93.4%)Acute toxicity (Oral) - Category 4Hazardous to the aquatic environment (Acute) - Category 3Hazardous to the aquatic environment (Long-term) - Category 3 |
| USGS Health-Based Screening Levels for Evaluating Water-Quality | IsoquinolineWaste-water effluent contaminantSmith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP |
| Personal protective equipment (PPE) | Eyeshields, Faceshields, Gloves, type P2 (EN 143) respirator cartridges |
| Water hazard class (WGK) | 2 |
| TSCA inventory status | TSCA listed |
| RTECS number | NW6825000 |
| UN transport number | UN 2811 6.1/PG 3 |
| Customs code | 29334900 |
| Toxicity | LD50 orally in rats: 360 mg/kg (Smyth) |
| Risk statements (R) | 22-24-38-52/53-36/38-21/22-45 |
| Signal word | Danger |
| GHS pictogram | GHS06 |
| Hazard symbols | T |
| Safety statements (S) | 36/37-45-36/37/39-61-53 |
| Hazard class | 6.1Acute Tox. 3 DermalAcute Tox. 4 OralAquatic Chronic 3Eye Irrit. 2Skin Irrit. 2 |
| Storage class | 6.1C - Combustible acute toxic Cat.3toxic compounds or compounds which causing chronic effects |
| Packing group | II |
| GHS hazard statements | H302-H311-H315-H319-H412 |
| REACH registrations | Active |
| GHS precautionary statements | P264-P273-P280-P301+P312-P302+P352+P312-P305+P351+P338 |
Applications & Uses
Description
Isoquinoline, also known as 2-azanaphthalene, benzo[c]pyridine, or 2-benzanine, is a structural isomer of quinoline. It has structural and spectroscopic properties similar to quinoline. Isoquinoline was first isolated in 1885 by Hoogewerf and van Dorp from the quinoline fraction of coal tar by fractional crystallization. It is used to prepare dyes, insecticides, and antimalarial compounds, among other things.
Uses
Isoquinolines are used in the manufacture of dyes, paints, insecticides and antifungals. It is also used as a solvent for the extraction of resins and terpenes, and as a corrosion inhibitor.Isoquinoline (isq) has been used:in the preparation of cis-[(dcbH2)2Ru(isq)2](ClO4)2 [dcbH2 = 4,4′-(CO2H)2-2,2′-bipyridine].to investigate the toxicity of three two-ring and five three-ring azaarenes to the green alga Scenedesmus acuminatus and its relationship with molecular structure.
General Description
Isoquinoline is one of the very few heterocyclic compounds in which numbering of the ring atoms does not start on the hetero atom.It consists of a benzene ring fused to the β- and Y-positions of a pyridine ring.Isoquinoline has an odor reminiscent of benzaldehyde and anise. Isoquinoline may be obtained from coal tar (238 - 250°C boiling fraction); it is isolated as the sulfate or as is by repeated freezing.
Preparation & Synthesis
Preparation
Bischler-Napieralski synthesis is used to synthesize isoquinolines. β-phenylethylamine is acylated, and then cyclodehydrated using phosphoryl chloride, phosphorus pentoxide or other Lewis acids to yield dihydroisoquinoline, which can be aromatized by dehydrogenation with palladium, for example in the synthesis of papaverine, a pharmacologically active isoquinoline alkaloid.Pictet-Spengler synthesis is another method of preparing isoquinolines. β-phenylethylamine reacts with an aldehyde to produce an imine, which undergoes acid-catalysed cyclization, resulting in the synthesis of the tetrahydroisoquinoline system. Again, tetrahydroisoquinoline can be aromatized by palladium dehydrogenation to produce an isoquinoline system.