104-49-4

Basic information

• Product Name: 1,4-Phenylene diisocyanate
• Synonyms: Phenylene diisocyanat;1,4-Phenylene diisocyate;BENZENE 1,4-DIISOCYANATE;1,4-PHENYLENE DIISOCYANATE;1,4-Benzenediisocyanate;1,4-diisocyanato-benzen;1,4-Diisocyanatobenzene;1,4-diisocyanato-Benzene
• CAS NO: 104-49-4
• Molecular Formula: C₈H₄N₂O₂
• Molecular Weight: 160.13
• EINECS: 203-207-6
• Product Categories: Building Blocks;Chemical Synthesis;Nitrogen Compounds;Organic Building Blocks;Resin additives;Isocyanates;Nitrogen Compounds;Organic Building Blocks
• Mol File: 104-49-4.mol
• Article Data: 14

Chemical Properties

• Melting Point: 96-99 °C(lit.)
• Boiling Point: 260 °C(lit.)
• Flash Point: >230 °F
• Appearance: white to light yellow crystals
• Density: 1.3848 (rough estimate)
• Vapor Pressure: <0.01 mm Hg ( 20 °C)
• Refractive Index: 1.4900 (estimate)
• Solubility: THF: soluble
• Water Solubility: 130mg/L at 20℃
• Stability: Stable. Combustible. Incompatible with strong oxidising agents, strong alkalies, strong acids, alcohols, amines. Moisture sensit
• CAS DataBase Reference: 1,4-Phenylene diisocyanate(CAS DataBase Reference)
• NIST Chemistry Reference: 1,4-Phenylene diisocyanate(104-49-4)
• EPA Substance Registry System: 1,4-Phenylene diisocyanate(104-49-4)

Safety Data

• Hazard Codes: Xn,C
• Statements: 20/21/22-36/37/38-42-34-41-38
• Safety Statements: 22-26-36/37-45-36/37/39
• RIDADR: UN 2811 6.1/PG 3
• WGK Germany: 3
• RTECS: CZ6150000
• HazardClass: 6.1
• PackingGroup: III
• Hazardous Substances Data: 104-49-4(Hazardous Substances Data)

Usage

Chemical Properties

white to light yellow crystals

Uses

1,4-Phenylene diisocyanate has been used:as croos-linking reagent to investigate the mechanism of enzyme immobilization on silanized surfacesin the synthesis of dipodal bis-urea receptor, a selective receptor for hydrogen sulfatein deposition of polyurea resists films via molecular layer deposition

Synthesis Reference(s)

Journal of Heterocyclic Chemistry, 7, p. 177, 1970 DOI: 10.1002/jhet.5570070126

General Description

White crystals or pale yellow chunky solid. Pungent odor.

Air & Water Reactions

Reacts slowly with water to form CO2

Reactivity Profile

1,4-Phenylene diisocyanate is sensitive to moisture. 1,4-Phenylene diisocyanate is incompatible with water, strong acids, strong alkalis, strong oxidizers, alcohol, amines and other hydrogen compounds.

Fire Hazard

1,4-Phenylene diisocyanate is combustible.

Flammability and Explosibility

Notclassified

InChI:InChI=1/C8H4N2O2/c11-5-9-7-1-2-8(4-3-7)10-6-12/h1-4H

Synthetic route

bis(trichloromethyl) carbonate (32315-10-9) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
In chlorobenzene at 55 - 130℃; for 18h; Temperature; Solvent;	97.8%

phosgene (75-44-5) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
Stage #1: 1,4-phenylenediamine With hydrogenchloride In 1,2-dichloro-benzene at 100℃; under 1125.11 Torr; for 1h; Flow reactor; Large scale; Stage #2: phosgene In 1,2-dichloro-benzene at 140℃; under 1125.11 Torr; for 3.5h; Flow reactor; Large scale;	97.5%
at 470℃;

5-{6-hydroxy-2-(4-hydroxyphenyl)-4-[2-(4-hydroxyphenyl)vinyl]-2,3-dihydrobenzofuran-3-yl}benzene-1,3-diol → 1,4-diisocyanatobenzene (104-49-4) + (+)-ampelopsin B + (-)-isoampelopsin D + CAS No: [151487-08-0]

Conditions	Yield
With sulfuric acid In methanol for 120h; Heating;	A 6% B 13% C 10% D 19%

phosgene (75-44-5) + p-phenylenediamine hydrochloride (540-24-9) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
at 200 - 250℃;

phosgene (75-44-5) + methylammonium carbonate (15719-64-9, 15719-76-3, 97762-63-5) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
at 470℃;

4,6-diphenylthieno-[3,4-d]-1,3-dioxol-2-one-5,5-dioxide (54714-11-3) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
(i), (ii) (thermolysis); Multistep reaction;

1,4-phenylenediamine (106-50-3) + trichloromethyl chloroformate (503-38-8) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
In 1,4-dioxane

terephthalonitrile (623-26-7) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
With (η5-C5H4SiMe3)2NbH(O)C=CPh2

carbon dioxide (124-38-9) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
With cyclohexyl-tetraethyl guanidine; triethylamine; trichlorophosphate 1.) acetonitrile, 80 psig, 2.) acetonitrile; Yield given. Multistep reaction;

dimethyl N,N′-(1,4-phenylene)dicarbamate (5433-04-5) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
With 2-chloro-1,3,2-benzodioxaborole; triethylamine In toluene 1.) reflux, 5 min, 2.) 0.5 h;	100 % Chromat.
With boron trichloride; triethylamine In benzene for 0.5h; Heating;	90 % Chromat.

diethyl 1,4-phenylenediamine-N,N'-dicarboxylate (5466-93-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
With boron trichloride; triethylamine In benzene for 0.5h; Heating;	100 % Chromat.

(4-Propoxycarbonylamino-phenyl)-carbamic acid propyl ester → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
With boron trichloride; triethylamine In benzene for 0.5h; Heating;	100 % Chromat.

hydrogenchloride (7647-01-0) + phosgene (75-44-5) + 1,4-phenylenediamine (106-50-3) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
at 200 - 250℃;

terephthalic acid diazide (14528-67-7) → 1,4-diisocyanatobenzene (104-49-4)

Conditions	Yield
In toluene at 80℃; for 2h; Inert atmosphere;

methanol (67-56-1) + 1,4-diisocyanatobenzene (104-49-4) → dimethyl N,N′-(1,4-phenylene)dicarbamate (5433-04-5)

Conditions	Yield
for 4h; Heating;	100%

1,4-diisocyanatobenzene (104-49-4) + butan-1-ol (71-36-3) → (4-Butoxycarbonylamino-phenyl)-carbamic acid butyl ester (130872-00-3)

Conditions	Yield
for 4h; Heating;	100%

1,4-diisocyanatobenzene (104-49-4) + 2-bromoaniline (615-36-1) → C20H16Br2N4O2

Conditions	Yield
With triethylamine In toluene at 20℃; for 19h;	100%

rimantadine (13392-28-4, 117857-51-9, 117857-52-0, 129277-01-6) + 1,4-diisocyanatobenzene (104-49-4) → 1,1'-(1,4-phenylene)bis{3-[1-(adamantan-1-yl)ethyl]urea} (1607795-41-4)

Conditions	Yield
In N,N-dimethyl-formamide at 15 - 25℃; for 6h;	99%

1,4-diisocyanatobenzene (104-49-4) + 2-amino-2-hydroxymethyl-1,3-propanediol (77-86-1) → N,N'-(1,4-phenylene)bis{N''-[tris(hydroxymethyl)methyl]urea} (1056030-11-5)

Conditions	Yield
In 1,4-dioxane; water at 20℃; for 2h;	98%

rimantadine hydrochloride (1501-84-4, 33122-80-4, 33122-81-5, 33298-76-9) + 1,4-diisocyanatobenzene (104-49-4) → 1,1'-(1,4-phenylene)bis{3-[1-(adamantan-1-yl)ethyl]urea} (1607795-41-4)

Conditions	Yield
With triethylamine In N,N-dimethyl-formamide at 0 - 25℃; for 12h; Inert atmosphere;	98%
With triethylamine In N,N-dimethyl-formamide at 0 - 25℃; for 12h; Inert atmosphere;

adamantan-2-amine hydrochloride (10523-68-9) + 1,4-diisocyanatobenzene (104-49-4) → 1,4-(phenylene)bis[(adamant-2-yl)urea]

Conditions	Yield
With triethylamine In N,N-dimethyl-formamide at 0 - 25℃; for 12h; Inert atmosphere;	98%

adamantylmethylamine (17768-41-1) + 1,4-diisocyanatobenzene (104-49-4) → 1,1'-(1,4-phenylene)bis[3-(adamantan-1-ylmethyl)urea] (1607795-33-4)

Conditions	Yield
In N,N-dimethyl-formamide at 15 - 25℃; for 6h;	98%

1,4-diisocyanatobenzene (104-49-4) → N,N',N''-tri(p-isocyanatophenyl)isocyanurate

Conditions	Yield
With C30H28AlN3O3 at 100℃; for 1.5h; Inert atmosphere; Glovebox; Sealed tube;	97%

9-amino-9-deoxy-epi-cinchonidine + 1,4-diisocyanatobenzene (104-49-4) → C27H27N5O2

Conditions	Yield
In chloroform for 16h; Reflux;	97%

C28H40O4S + 1,4-diisocyanatobenzene (104-49-4) → C64H84N2O10S2

Conditions	Yield
With dibutyltin dilaurate In toluene at 60℃; for 4h; Inert atmosphere;	96.3%

1,4-diisocyanatobenzene (104-49-4) → 1,1'-(p-phenylene)bis(urea) (1205-90-9)

Conditions	Yield
With ammonium hydroxide In water at 0 - 20℃; for 2.5h;	96%
With ammonia

1,4-diisocyanatobenzene (104-49-4) + 1-(adamantan-1-yl)-2-aminobutane (779989-20-7) → 1,1'-(1,4-phenylene)bis{3-[1-(adamantan-1-yl)butan-2-yl]urea}

Conditions	Yield
In N,N-dimethyl-formamide at 15 - 25℃; for 6h;	96%

tetrahydrogeraniol (106-21-8, 59204-02-3) + 1,4-diisocyanatobenzene (104-49-4) → [4-(3,7-dimethyl-octyloxycarbonylamino)-phenyl]-carbamic acid 3,7-dimethyl-octyl ester

Conditions	Yield
With 1,4-diaza-bicyclo[2.2.2]octane In benzene at 50℃; for 1h;	95%

1,4-diisocyanatobenzene (104-49-4) + 3-Amino-3-((3aS,5R,6R,6aS)-6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester → 3-(6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-3-[3-(4-{3-[1-(6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-2-ethoxycarbonyl-ethyl]-ureido}-phenyl)-ureido]-propionic acid ethyl ester

Conditions	Yield
In dichloromethane at 20℃; for 2h;	95%

1,4-diisocyanatobenzene (104-49-4) + 3-Amino-3-((3aS,6R,6aS)-6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester → 3-[3-(4-{3-[2-Ethoxycarbonyl-1-((3aS,6R,6aS)-6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-ethyl]-ureido}-phenyl)-ureido]-3-((3aS,6R,6aS)-6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester

Conditions	Yield
In dichloromethane at 20℃; for 12h;	95%

1,4-diisocyanatobenzene (104-49-4) + 3-Amino-3-((3aS,6R,6aS)-6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester → 3-((3aS,6R,6aS)-6-Benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-3-[3-(4-{3-[1-((3aS,6R,6aS)-6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-2-ethoxycarbonyl-ethyl]-ureido}-phenyl)-ureido]-propionic acid ethyl ester

Conditions	Yield
In dichloromethane at 20℃; for 12h;	95%

1,4-diisocyanatobenzene (104-49-4) + L-tryptophan methyl ester (4299-70-1) → C32H32N6O6

Conditions	Yield
In dichloromethane for 12h; Cooling with ice;	94.92%

1,4-diisocyanatobenzene (104-49-4) + L-proline (147-85-3) → N,N′-[1,4-phenylenebis(iminocarbonyl)]di(L-proline)

Conditions	Yield
With sodium hydroxide In water; toluene at 0℃; for 4h;	94%

1-(2-hydroxyethyl)pyridinium bis(trifluoromethanesulfonyl)azanide (752260-02-9) + 1,4-diisocyanatobenzene (104-49-4) → 1-{2-[N-(4-isocyanatophenyl)carbamoyloxy]ethyl}pyridinium bis(trifluoromethanesulfonyl)imide

Conditions	Yield
With dibutyltin dilaurate In acetonitrile at 50℃; for 6h;	93.54%

1,4-diisocyanatobenzene (104-49-4) + isopropyl alcohol (67-63-0) + (S)-6,6'-diaminomethyl-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl → polymer, DP = 10, av. M ca. 12000; monomer(s): 6,6\-di(aminomethyl)-2,2\-bis(diphenylphosphinyl)-1,1\-binaphthyl; 2,6-diisocyanatotoluene; isopropanol

Conditions	Yield
Stage #1: 1,4-diisocyanatobenzene; (S)-6,6'-diaminomethyl-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl In dichloromethane Stage #2: isopropyl alcohol	93%

N,N,N-trimethyl-N-(2-hydroxyethyl)ammonium bis(trifluoromethanesulfonyl)imide (827027-25-8) + 1,4-diisocyanatobenzene (104-49-4) → 2-[N-(4-isocyanatophenyl)carbamoyloxy]ethyltrimethylammonium bis(trifluoromethanesulfonyl)imide

Conditions	Yield
With dibutyltin dilaurate In acetonitrile at 50℃; for 6h;	92.21%

1,4-diisocyanatobenzene (104-49-4) + 3-Benzylamino-3-((3aS,6R,6aS)-6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester → 3-[1-benzyl-3-(4-{3-benzyl-3-[1-(6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-2-ethoxycarbonyl-ethyl]-ureido}-phenyl)-ureido]-3-(6-benzyloxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester

Conditions	Yield
In dichloromethane at 20℃; for 12h;	92%

1,4-diisocyanatobenzene (104-49-4) + diphenylphosphane (829-85-6) → C32H26N2O2P2

Conditions	Yield
In neat (no solvent) at 80℃; for 12h; Schlenk technique; Inert atmosphere;	92%

4-aminobutyrylaldehyde diethylacetal (6346-09-4) + 1,4-diisocyanatobenzene (104-49-4) → 1,1'-(benzene-1,4-diyl)bis[3-(4,4-diethoxybutyl)-urea] (1620286-16-9)

Conditions	Yield
In toluene for 96h;	91%

1,4-diisocyanatobenzene (104-49-4) + 3-Benzylamino-3-((3aS,6R,6aS)-6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester → 3-[1-benzyl-3-(4-{3-benzyl-3-[2-ethoxycarbonyl-1-(6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-ethyl]-ureido}-phenyl)-ureido]-3-(6-methoxy-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-5-yl)-propionic acid ethyl ester

Conditions	Yield
In dichloromethane at 20℃; for 12h;	90%

3,4,4-trimethyl-2-methyleneoxazolidine (159064-15-0) + 1,4-diisocyanatobenzene (104-49-4) → 2-(3,4,4-trimethyl-oxazolidin-2-ylidene)-N-{4-[2-(3,4,4-trimethyl-oxazolidin-2-ylidene)-acetylamino]-phenyl}-acetamide

Conditions	Yield
In tetrahydrofuran at 24℃;	90%

[(η(5)-C5H4SiMe3)2Nb(μ-Cl)]2 (118345-02-1) + 1,4-diisocyanatobenzene (104-49-4) → [(Nb(C5H4Si(CH3)3)2Cl)2(OCNC6H4NCO)]

Conditions	Yield
In pentane (inert atmosphere); stirring (room temp., overnight); filtration, drying (vac.); elem. anal.;	90%

Upstream product

• 54714-11-3 4,6-diphenylthieno-[3,4-d]-1,3-dioxol-2-one-5,5-dioxide 
• 106-50-3 1,4-phenylenediamine 
• 503-38-8 trichloromethyl chloroformate 
• 5433-04-5 dimethyl N,N′-(1,4-phenylene)dicarbamate 
• 5466-93-3 diethyl 1,4-phenylenediamine-N,N'-dicarboxylate 
• 32315-10-9 bis(trichloromethyl) carbonate 
• 14528-67-7 terephthalic acid diazide 
• 253435-07-3 5-{6-hydroxy-2-(4-hydroxyphenyl)-4-[2-(4-hydroxyphenyl)vinyl]-2,3-dihydrobenzofuran-3-yl}benzene-1,3-diol 
• 7647-01-0 hydrogenchloride 
• 75-44-5 phosgene 
• 124-38-9 carbon dioxide 
• 623-26-7 terephthalonitrile 
• 15719-64-9 methylammonium carbonate 
• 540-24-9 p-phenylenediamine hydrochloride 

Downstream Products

• 4685-16-9 N,N'-bis-(aziridine-1-carbonyl)-p-phenylenediamine 
• 5433-04-5 dimethyl N,N′-(1,4-phenylene)dicarbamate 
• 102811-20-1 N,N'-p-phenylene-bis-carbamic acid bis-(2-oxo-1-propyl-pentyl ester) 
• 5466-93-3 diethyl 1,4-phenylenediamine-N,N'-dicarboxylate 
• 36369-22-9 1,4-bis-(phenyl-trans-azo)-benzene 
• 1205-90-9 1,1'-(p-phenylene)bis(urea) 
• 475652-78-9 [4-((3R,7R)-3,7,11-Trimethyl-dodecyloxycarbonylamino)-phenyl]-carbamic acid (3R,7R)-3,7,11-trimethyl-dodecyl ester 
• 862251-08-9 C₅₀H₆₆N₄O₆ 

Relevant articles and documents

Isocyanates From Primary Amines and Carbon Dioxide: 'Dehydration' of Carbamate Anions

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Preparation method of p-phenyl diisocyanate

The invention provides a preparation method of p-phenylene diisocyanate. The preparation method comprises the following steps that: p-phenylenediamine is dissolved in a low-boiling-point solvent undernormal temperature to 65 DEG C, so that a p-phenylenediamine solution can be prepared; di-(trichloromethyl) carbonate is dissolved in a high-boiling-point solvent, so that a di-(trichloromethyl) carbonate solution can be prepared; the p-phenylenediamine solution and the di-(trichloromethyl) carbonate solution are mixed, the mixed solution is subject to a reaction; and after the mixed solution issubjected to three reaction stages of cold light (from the normal temperature to 40 DEG C), warm light (50-80 DEG C) and hot light (110-180 DEG C), the p-phenylene diisocyanate can be obtained. According to the method, the p-phenylenediamine and the di-(trichloromethyl) carbonate are respectively dissolved by adopting the two solvents with different boiling points, and therefore, reaction energy consumption is effectively reduced, the purity of the obtained p-phenylenediamine is up to 99% through the three reaction stages; and the yield of the p-phenylenediamine is up to 97.8%.