553-94-6

Basic information

• Product Name: 2,5-Dimethylbromobenzene
• Synonyms: 1,4-Dimethyl-2-bromobenzene;2,5-Dimethyl-1-bromobenzene;2-Bromo-p-xylene,97%;2-BroMo-p-xylene, 97% 100GR;DiMethylbroMobenzene;1,4-DiMethyl-2-broMobenzene[2,5-DiMethylbroMobenzene];2,5- twodiMethylbroMobenzene;2-Bromo-p-xylene
• CAS NO: 553-94-6
• Molecular Formula: C₈H₉Br
• Molecular Weight: 185.06
• EINECS: 209-055-7
• Product Categories: Halogen toluene;Benzene derivates;Bromine Compounds;Aromatic Hydrocarbons (substituted) & Derivatives
• Mol File: 553-94-6.mol
• Article Data: 46

Chemical Properties

• Melting Point: 9-10 °C(lit.)
• Boiling Point: 199-201 °C(lit.)
• Flash Point: 175 °F
• Appearance: Clear colorless to slightly colored/Liquid
• Density: 1.34 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.481mmHg at 25°C
• Refractive Index: n20/D 1.550(lit.)
• Storage Temp.: Keep in dark place,Sealed in dry,Room Temperature
• BRN: 2040350
• CAS DataBase Reference: 2,5-Dimethylbromobenzene(CAS DataBase Reference)
• NIST Chemistry Reference: 2,5-Dimethylbromobenzene(553-94-6)
• EPA Substance Registry System: 2,5-Dimethylbromobenzene(553-94-6)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36/37/39-24/25
• RIDADR: UN 2810 6.1/PG 3
• WGK Germany: 3
• TSCA: Yes
• Hazardous Substances Data: 553-94-6(Hazardous Substances Data)

Usage

Chemical Properties

Clear colourless to light yellow liquid

Uses

2-Bromo-1,4-dimethylbenzene was used in the synthesis of 2,5,2′,5′-tetrakismethylbiphenyl via Yamamoto coupling reaction. It was also used in the synthesis of cis-3,4-diphenyl-5,8-dimethylisocoumarins.

InChI:InChI=1/C8H9Br/c1-6-3-4-7(2)8(9)5-6/h3-5H,1-2H3

Synthetic route

para-xylene (106-42-3) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With potassium bromide; sodium nitrite In water; trifluoroacetic acid at 20℃; for 0.16h; Product distribution; under argon;	100%
With oxygen; potassium bromide; sodium nitrite In water; trifluoroacetic acid at 20℃; for 5h; Product distribution;	96%
With sulfuric acid; dihydrogen peroxide; sodium bromide In water at 49.84℃;	94%

para-xylene (106-42-3) → 4-bromo-m-xylene (553-94-6) + 2,5-dibromo-p-xylene (1074-24-4)

Conditions	Yield
With carbon dioxide; bromine at 40℃; under 187519 Torr; for 2h; Supercritical conditions; Green chemistry;	A 92% B 8%
With aluminum oxide; bromine for 0.0166667h; Ambient temperature; Yield given. Yields of byproduct given. Title compound not separated from byproducts;
With N-Bromosuccinimide at 20℃; for 16h; Overall yield = 85 %Spectr.; regioselective reaction;

para-xylene (106-42-3) → 4-bromo-m-xylene (553-94-6) + 2,5-dibromo-p-xylene (1074-24-4) + 4-Methylbenzyl bromide (104-81-4)

Conditions	Yield
With bromine; acetic acid	A 77% B 10% C 13%
With bromine	A 48% B n/a C n/a

para-xylene (106-42-3) → 4-bromo-m-xylene (553-94-6) + 4-Methylbenzyl bromide (104-81-4)

Conditions	Yield
With sodium bromate; sodium hydrogensulfite In water; acetonitrile at 20℃; for 4h; Bromination;	A 62% B n/a
With bromine; bentonite In carbon disulfide for 4h; Heating;	A 50% B 30%
With N-Bromosuccinimide In methanol at 150℃; under 2625.26 Torr; for 0.0666667h; microwave irradiation;	A 27 % Chromat. B 32 % Chromat.
With hydrogen bromide; dihydrogen peroxide In water at 20℃; for 24h; Darkness;	A 66 %Spectr. B 14 %Spectr.
With N-Bromosuccinimide; silver hexafluoroantimonate; adamantan-1-yl(methyl)sulfane In 1,2-dichloro-ethane at 20℃; for 1h; Inert atmosphere; Schlenk technique;	A 50 %Chromat. B 20 %Chromat.

1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dimethylbenzene (356570-53-1) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With copper(ll) bromide In methanol Heating;	46%

2,5-Dimethylaniline (95-78-3) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With hydrogen bromide diazotization;	40%
(i) (diazotization), aq. HBr, (ii) Cu; Multistep reaction;

Methyl fluoride (593-53-3) + 2-methylphenyl bromide (95-46-5) → 2-Bromo-m-xylene (576-22-7) + 4-bromo-m-xylene (553-94-6) + 1-bromo-2,4-dimethylbenzene (583-70-0) + 2,3-dimethylbromobenzene (576-23-8)

Conditions	Yield
With oxygen at 40℃; under 720 Torr; Mechanism; Irradiation;	A n/a B n/a C 13.7% D 32.8%

2,5-dimethylbenzenesulfonic acid (609-54-1) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With copper(ll) bromide

2,2,2-trifluoroethanol (75-89-8) + (E)-1,4-Dimethyl-1,3-hexadien-5-in-1-yl-triflat (93362-61-9) → 4-bromo-m-xylene (553-94-6) + (4-Methylbenzyl)-(2,2,2-trifluorethyl)-ether (79644-39-6) + (Z)-3-Methyl-hept-3-ene-1,5-diyne (79644-36-3) + (2,5-Dimethylphenyl)-(2,2,2-trifluorethyl)-ether (79644-38-5)

Conditions	Yield
With 1,3,5-triisopropyl benzene; sodium carbonate; lithium bromide In 1,4-dioxane; water at 120℃; for 120h; Mechanism; Product distribution;	A 17 % Chromat. B 14 % Chromat. C n/a D 14 % Chromat.

para-xylene (106-42-3) → 4-bromo-m-xylene (553-94-6) + 2,6-dibromo-1,4-dimethylbenzene (66788-13-4)

Conditions	Yield
With aluminum oxide; copper(ll) bromide In tetrachloromethane at 80℃; for 1.5h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

para-xylene (106-42-3) → 4-Methylbenzyl alcohol (589-18-4) + 4-bromo-m-xylene (553-94-6) + 1,4-dimethyl-2-(4-methylbenzyl)benzene (721-45-9) + 4-methyl-benzaldehyde (104-87-0)

Conditions	Yield
With sulfuric acid; hydrogen bromide In water; acetic acid at 90℃; for 1h; Product distribution; Mechanism; other solvent, effect of the absence of HBr;	A 65 % Chromat. B 30 % Chromat. C 71 % Chromat. D 22 % Chromat.

3-methylbicyclo<4.1.0>hepta-1,3,5-triene (75366-05-1) → 4-bromo-m-xylene (553-94-6) + 1-bromo-2,4-dimethylbenzene (583-70-0)

Conditions	Yield
With bromine; tri-n-butyl-tin hydride Product distribution; Mechanism; multistep reaction; reaction regioselectivity; a series of reagents;

(E)-1,4-Dimethyl-1,3-hexadien-5-in-1-yl-triflat (93362-61-9) → 4-bromo-m-xylene (553-94-6) + (4-Methylbenzyl)-(2,2,2-trifluorethyl)-ether (79644-39-6) + (2,5-Dimethylphenyl)-(2,2,2-trifluorethyl)-ether (79644-38-5) + 2,5-dimethylphenyl trifluoromethanesulfonate (79644-40-9)

Conditions	Yield
With 2,2,2-trifluoroethanol; sodium carbonate; lithium bromide In 1,4-dioxane; water at 100℃; for 120h; Further byproducts given;	A 16.6 % Chromat. B 41.2 % Chromat. C 14.4 % Chromat. D 1 % Chromat.

para-xylene (106-42-3) + iodine (7553-56-2) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
beim Bromieren;

para-xylene (106-42-3) + iodine (7553-56-2) → 4-bromo-m-xylene (553-94-6) + 2,5-dibromo-p-xylene (1074-24-4)

Conditions	Yield
beim Bromieren;

para-xylene (106-42-3) + iodine (7553-56-2) → 4-bromo-m-xylene (553-94-6) + 2,5-dibromo-p-xylene (1074-24-4) + 2,3,5,6-tetrabromo-p-xylene (23488-38-2)

Conditions	Yield
beim Bromieren;

diazotized 2-amino-p-xylene → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With hydrogen bromide; copper(I) bromide

2,5-Dimethylphenol (95-87-4) + platinum → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
Multi-step reaction with 3 steps 1: 93 percent / pyridine / CH2Cl2 / 0.25 h / 0 °C 2: 99 percent / Et3N / PdCl2(dppf) / dioxane / Heating 3: 46 percent / aq. CuBr2 / methanol / Heating View Scheme

2,5-dimethylphenyl trifluoromethanesulfonate (79644-40-9) → 4-bromo-m-xylene (553-94-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: 99 percent / Et3N / PdCl2(dppf) / dioxane / Heating 2: 46 percent / aq. CuBr2 / methanol / Heating View Scheme

2,3-dibromo-1,4-dimethylbenzene (15540-84-8) → para-xylene (106-42-3) + 4-bromo-m-xylene (553-94-6)

Conditions	Yield
With tris(2,2'-bipyridine)ruthenium(II) perchlorate; triethanolamine; Ni((C6H5)CH2O)(C5H2N)(CH2)2(NHCH2CH2CH2)2NH(2+) In acetonitrile at 25℃; for 3h; Photolysis;
With nickel(II) 1,4,8,11-tetraazacyclotetradecane; tris(2,2'-bipyridine)ruthenium(II) perchlorate; triethanolamine In acetonitrile at 25℃; for 3h; Photolysis;

4-bromo-m-xylene (553-94-6) + triethyl phosphite (122-52-1) → (2,5-dimethylphenyl)diethyl phosphonate (58983-18-9)

Conditions	Yield
With nickel dibromide at 160℃; for 2h; Inert atmosphere;	100%
Irradiation;

2-tert-Butylphenol (88-18-6) + 4-bromo-m-xylene (553-94-6) → 3-tert-butyl-2',5'-dimethylbiphenyl-2-ol

Conditions	Yield
With tris(triphenylphosphine)rhodium(I) chloride; caesium carbonate; diisopropyl(2-tert-butyl)phenoxyphosphine In toluene for 18h; Heating;	100%
With caesium carbonate; diisopropyl(2-tert-butyl)phenoxyphosphine; RhCl(PPh3)3 In toluene for 18h; Heating;	100%
With caesium carbonate; chloro(1,5-cyclooctadiene)rhodium(I) dimer In toluene for 18h; Heating;	94 % Spectr.

triisopropyl phosphite (116-17-6) + 4-bromo-m-xylene (553-94-6) → (2,5-dimethylphenyl)diisopropyl phosphonate

Conditions	Yield
With nickel dibromide at 150℃; for 3h; Inert atmosphere;	100%

4-bromo-m-xylene (553-94-6) + 2-chloropropionyl chloride (625-36-5) → 4-bromo-1-(3'-chloro-1'-oxopropyl)-2,5-dimethylbenzene (246022-83-3)

Conditions	Yield
Stage #1: 2-chloropropionyl chloride With aluminum (III) chloride In dichloromethane for 0.25h; Schlenk technique; Inert atmosphere; Stage #2: 4-bromo-m-xylene In dichloromethane at 20℃; for 20h; Inert atmosphere;	99%
With aluminium trichloride In dichloromethane at 50℃; for 3h; Addition;	87%
With aluminum (III) chloride In carbon disulfide at 0℃; for 1h; Reflux;	61%
With aluminium trichloride In carbon disulfide at 20℃; for 16h;

4-bromo-m-xylene (553-94-6) + 2-Methylphenylboronic acid (16419-60-6) → 2,5,2'-trimethyl-1,1'-biphenyl (76708-72-0)

Conditions	Yield
With Merrifield resin-bound dicyclohexylphosphinobiphenyl ligand; caesium carbonate; tris(dibenzylideneacetone)dipalladium (0) In tetrahydrofuran at 65℃; Suzuki reaction;	99%

4-bromo-m-xylene (553-94-6) + 1-amino-3-methylbenzene (108-44-1) → N-(2,5-dimethylphenyl)-m-toluidine

Conditions	Yield
With Merrifield resin-bound dicyclohexylphosphinobiphenyl ligand; sodium t-butanolate; tris(dibenzylideneacetone)dipalladium (0) In toluene at 100℃;	99%

4-bromo-m-xylene (553-94-6) + 2-phenylaniline (90-41-5) → 2,5-dimethyl-2'-phenyldiphenylamine

Conditions	Yield
With palladium diacetate; P(i-BuNCH2CH2)3N; sodium t-butanolate In toluene at 80℃;	99%

4-bromo-m-xylene (553-94-6) + chloroacetyl chloride (79-04-9) → 2-(2,5-dimethylphenyl)acetyl chloride (55312-97-5)

Conditions	Yield
Stage #1: 4-bromo-m-xylene; chloroacetyl chloride With hydrogenchloride; ruthenium(IV) oxide; palladium 10% on activated carbon In dimethyl sulfoxide at 100℃; for 5h; Stage #2: With sodium sulfite In water; dimethyl sulfoxide at 135℃; for 8.25h; Temperature;	98.1%

1-methyl-piperazine (109-01-3) + 4-bromo-m-xylene (553-94-6) → 1-(2,5-dimethylhenyl)-4-methylpiperazine

Conditions	Yield
With tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; sodium t-butanolate In toluene at 80℃; for 4h;	98%
With tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; sodium t-butanolate at 80℃; for 4h; Arylation;	98%
With tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; sodium t-butanolate In neat (no solvent) at 80℃; for 4h; Inert atmosphere;	98%
With tris(dibenzylideneacetone)dipalladium (0); sodium isopropylate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 110℃; for 7h; Substitution;	68%

4-bromo-m-xylene (553-94-6) + p-toluidine (106-49-0) → N-(4-methylphenyl)-2,5-dimethylaniline (34160-15-1)

Conditions	Yield
With bis[2-(diphenylphosphino)phenyl] ether; sodium t-butanolate; palladium dichloride In toluene at 80℃; for 17h;	98%
With palladium diacetate; bis[2-(diphenylphosphino)phenyl] ether; sodium t-butanolate In toluene at 80℃; for 3h;	95%
With tris-(dibenzylideneacetone)dipalladium(0); tri-tert-butyl phosphine; sodium t-butanolate In toluene at 110℃; for 4h; Inert atmosphere;	67%

4-bromo-m-xylene (553-94-6) → bis(2,5-dimethylphenyl) sulfide (35019-02-4)

Conditions	Yield
With tris-(dibenzylideneacetone)dipalladium(0); caesium carbonate; thiourea; [2-((diphenylphospino)methyl)-2-methyl-1,3-propanediyl]bis[diphenylphosphine] In 1,4-dioxane at 100℃; for 18h; Inert atmosphere;	98%

lithium trimethoxy(1,2,2-trifluorovinyl)borate + 4-bromo-m-xylene (553-94-6) → 1,4-dimethyl-2-(1,2,2-trifluorovinyl)benzene (1361925-73-6)

Conditions	Yield
With potassium phosphate; tris-(dibenzylideneacetone)dipalladium(0); XPhos In tetrahydrofuran at 20 - 80℃; for 15.25h; Suzuki coupling; Inert atmosphere;	98%

2-bromoacetyl chloride (22118-09-8) + 4-bromo-m-xylene (553-94-6) → 2-(2,5-dimethylphenyl)acetyl chloride (55312-97-5)

Conditions	Yield
Stage #1: 2-bromoacetyl chloride; 4-bromo-m-xylene With hydrogenchloride; ruthenium(IV) oxide; palladium 10% on activated carbon In dimethyl sulfoxide at 100℃; for 5h; Stage #2: With sodium sulfite In water; dimethyl sulfoxide at 135℃; for 8.25h;	97.1%

dimethylmonochlorosilane (1066-35-9) + 4-bromo-m-xylene (553-94-6) → (2,5-dimethylphenyl)dimethylsilane

Conditions	Yield
Stage #1: 4-bromo-m-xylene With n-butyllithium In tetrahydrofuran at -78℃; for 3h; Inert atmosphere; Stage #2: dimethylmonochlorosilane In tetrahydrofuran at -78 - 20℃;	97%
With tert.-butyl lithium In diethyl ether; pentane 1.) -78 deg C, 2.) -78 deg C to 20 deg C, 2 h; Yield given;

morpholine (110-91-8) + 4-bromo-m-xylene (553-94-6) → 4-(2,5-dimethylphenyl)morpholine

Conditions	Yield
With tris(dibenzylideneacetone)dipalladium (0); (-)-2-(dicyclohexylphosphino)-2'-(dimethylamino)-1,1'-binaphthyl; sodium t-butanolate In 1,2-dimethoxyethane Ambient temperature;	97%
With potassium hexamethylsilazane In 1,4-dioxane at 100℃; for 0.25h; metal-free Buchwald-Hartwig amination; Inert atmosphere;	88 %Chromat.

4-bromo-m-xylene (553-94-6) + 2-methoxy-phenylamine (90-04-0) → N-(2-methoxyphenyl)-2,5-dimethylaniline

Conditions	Yield
With tris(dibenzylideneacetone)dipalladium (0); sodium isopropylate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 110℃; for 19h; Substitution;	97%
With bis[2-(diphenylphosphino)phenyl] ether; sodium t-butanolate; palladium dichloride In toluene at 80℃; for 4h;	93%
With palladium diacetate; bis[2-(diphenylphosphino)phenyl] ether; sodium t-butanolate In toluene at 80℃; for 21h;	90%

4-bromo-m-xylene (553-94-6) + trans-2-phenylvinylboronic acid (6783-05-7) → (E)-2,5-dimethyl-1-styrylbenzene (19290-86-9, 21162-42-5)

Conditions	Yield
With dicyclohexyl-(2',6'-dimethoxybiphenyl-2-yl)-phosphane; potassium phosphate; palladium diacetate In tetrahydrofuran at 40℃; for 24h; Suzuki-Miyaura coupling;	97%

4-bromo-m-xylene (553-94-6) + 1-Naphthylboronic acid (13922-41-3) → 1-(2,5-dimethylphenyl)naphthalene (131117-61-8)

Conditions	Yield
With potassium phosphate; C29H37O2P; palladium diacetate In toluene at 110℃; for 3h; Suzuki-Miyaura Coupling; Inert atmosphere; Schlenk technique;	97%

4-bromo-m-xylene (553-94-6) + ortho-cresol (95-48-7) → 1,4-dimethyl-2-(o-tolyloxy)benzene

Conditions	Yield
With palladium diacetate; potassium phosphate; 2-N,N-(dimethylamino)-2'-di-tert-butylphosphino-1,1'-binaphthyl In toluene at 100℃; for 24h;	96%
With potassium phosphate; tert-butyl XPhos; palladium diacetate In toluene at 100℃; for 24h;	92%
With potassium phosphate; 2-di-tert-butylphosphino-2',4',6'-tricyclohexyl-3,6-dimethoxybiphenyl In 1,2-dimethoxyethane; toluene at 40℃; for 24h; Inert atmosphere;	80%

4-bromo-m-xylene (553-94-6) + N-methylaniline (100-61-8) → N-methyl-N-phenyl-2,5-dimethylbenzenamine

Conditions	Yield
With tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; sodium t-butanolate at 80℃; for 36h; Arylation;	95%
With tris-(dibenzylideneacetone)dipalladium(0); 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl; sodium t-butanolate In toluene at 80℃; for 36h;	94%
With tris(dibenzylideneacetone)dipalladium (0); sodium isopropylate; 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl In toluene at 110℃; for 22h; Substitution;	85%

4-bromo-m-xylene (553-94-6) + 4-Chlorophenylboronic acid (1679-18-1) → 4’-chloro-2,5-dimethyl-1,1’-biphenyl (71149-93-4)

Conditions	Yield
With potassium phosphate; monophosphine 1,2,3,4,5-pentaphenyl-1'-(di-tert-butylphosphino)ferrocene; bis(dibenzylideneacetone)-palladium(0) In toluene at 100℃; for 14h; Suzuki coupling;	95%
With potassium phosphate; monophosphine 1,2,3,4,5-pentaphenyl-1'-(di-tert-butylphosphino)ferrocene; bis(dibenzylideneacetone)-palladium(0) In toluene	95%

4-bromo-m-xylene (553-94-6) + bicyclo[2.2.1]hepta-2,5-diene (121-46-0) → C23H24

Conditions	Yield
With palladium diacetate; caesium carbonate; triphenylphosphine In toluene at 20 - 115℃; for 5h; Temperature; Reagent/catalyst; Solvent; Sealed tube; stereoselective reaction;	95%

4-bromo-m-xylene (553-94-6) + acrylic acid methyl ester (292638-85-8) → methyl 3-(2,5-dimethylphenyl)prop-2-enoate

Conditions	Yield
With N-Methyldicyclohexylamine; 2C32H41O4P*Pd(2+)*2Cl(1-) In N,N-dimethyl acetamide at 100℃; for 16h; Heck Reaction; Inert atmosphere;	95%

oxirane (75-21-8) + 4-bromo-m-xylene (553-94-6) → 2-(2,5-dimethylphenyl)ethan-1-ol (6972-51-6)

Conditions	Yield
Stage #1: 4-bromo-m-xylene With iodine; magnesium In diethyl ether at 60℃; for 1h; Inert atmosphere; Stage #2: oxirane In diethyl ether at 0℃; for 3h; Temperature; Inert atmosphere;	94.69%
(i) Mg, Et2O, (ii) /BRN= 102378/; Multistep reaction;

4-bromo-m-xylene (553-94-6) + phenylboronic acid (98-80-6) → 2,5-dimethylbiphenyl (7372-85-2)

Conditions	Yield
With palladium diacetate; potassium fluoride; johnphos In tetrahydrofuran at 45℃; for 12h; Suzuki coupling;	94%
With potassium phosphate; Pd (sulfur-containing palladacycle); tetra(n-tert-butyl)ammonium bromide In N,N-dimethyl-formamide at 25℃; for 38h; Suzuki cross-coupling;	94%
With Pd(4,4'-bis(diphenylphosphino)-2,2',6,6'-tetra-methoxy-3,3'-bipyridine)Cl2; potassium hydroxide In ethanol; dichloromethane at 25℃; for 6h; Suzuki-Miyaura Coupling;	94%

4-bromo-m-xylene (553-94-6) + phenylacetylene (536-74-3) → 1,4-dimethyl-2-(phenylethynyl)benzene (29778-30-1)

Conditions	Yield
With potassium phosphate; bis(η3-allyl-μ-chloropalladium(II)); N,N,N′,N′-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine In 1,4-dioxane at 105℃; for 20h; Sonogashira coupling; Inert atmosphere;	94%
With dichloro[1-(2,4,6-trimethylbenzyl)-3-(4-adamantylbenzyl)-5,6-dimethylbenzimidazole-2-ylidene]triphenylphosphine palladium(II); potassium tert-butylate In N,N-dimethyl-formamide at 100℃; for 3h; Reagent/catalyst; Sonogashira Cross-Coupling; Schlenk technique;	94%
With potassium phosphate; bis(η3-allyl-μ-chloropalladium(II)); tetraphosphine N,N,N′,N′-tetra(diphenylphosphinomethyl)-pyridine-2,6-diamine In N,N-dimethyl acetamide; water at 100℃; for 20h; Sonogashira Cross-Coupling; Schlenk technique; Inert atmosphere;	93%

2,6-bis-(toluene-4-sulfonyl)-[1,5,2,6]dithiadiazocane (23516-76-9) + 4-bromo-m-xylene (553-94-6) → C17H21NO2S2

Conditions	Yield
Stage #1: 4-bromo-m-xylene With n-butyllithium In tetrahydrofuran at -78℃; for 1h; Inert atmosphere; Stage #2: 2,6-bis-(toluene-4-sulfonyl)-[1,5,2,6]dithiadiazocane In tetrahydrofuran for 0.5h; Inert atmosphere;	94%

pyrrolidine (123-75-1) + 4-bromo-m-xylene (553-94-6) → N-(2,5-xylyl)pyrrolidine (97053-04-8)

Conditions	Yield
With palladium diacetate; caesium carbonate; (S)-(1,1'-binaphthalene)-2,2'-diylbis(diphenylphosphine) In 1,4-dioxane at 100℃; for 17h; Arylation;	93%
With pyridine; bis(1,5-cyclooctadiene)nickel (0); 1,10-Phenanthroline; sodium t-butanolate at 100℃; Glovebox; Inert atmosphere;	8 %Chromat.

4-bromo-m-xylene (553-94-6) + 1-amino-2-propene (107-11-9) → N-allyl-2,5-xylidine (13519-81-8)

Conditions	Yield
With tris-(dibenzylideneacetone)dipalladium(0); johnphos; sodium t-butanolate; tris(dibenzylideneacetone)dipalladium (0) In toluene at 80℃; for 6h; Arylation;	93%

Upstream product

• 609-54-1 2,5-dimethylbenzenesulfonic acid 
• 95-78-3 2,5-Dimethylaniline 
• 75-89-8 2,2,2-trifluoroethanol 
• 93362-61-9 (E)-1,4-Dimethyl-1,3-hexadien-5-in-1-yl-triflat 
• 106-42-3 para-xylene 
• 7553-56-2 iodine 
• 15540-84-8 2,3-dibromo-1,4-dimethylbenzene 
• 79644-40-9 2,5-dimethylphenyl trifluoromethanesulfonate 
• 95-87-4 2,5-Dimethylphenol 
• 356570-53-1 1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dimethylbenzene 
• 75366-05-1 3-methylbicyclo<4.1.0>hepta-1,3,5-triene 
• 593-53-3 Methyl fluoride 
• 95-46-5 2-methylphenyl bromide 

Downstream Products

• 18415-06-0 (2,5-dimethylphenyl)triethoxysilane 
• 15540-81-5 1-bromo-2,5-dimethyl-4-nitrobenzene 
• 13014-24-9 3,4-dichloro-1-trichloromethylbenzene 
• 586-35-6 2-bromo-1,4-benzenedicarboxylic acid 
• 115034-38-3 tris(2,5-dimethylphenyl)phosphine 
• 2417-86-9 tris-(2,5-dimethyl-phenyl)-arsine 
• 6289-66-3 (+/-)-1r-(2.5-Dimethyl-phenyl)-cyclohexanol-(2t) 
• 699119-05-6 1-bromo-4-iodo-2,5-dimethylbenzene 
• 871876-77-6 2-bromo-1,4-bis-tribromomethyl-benzene 
• 5353-24-2 Bi{2,5-(CH₃)2C₆H₃}3 
• 101436-74-2 bis-(2,5-dimethyl-phenyl)-mercury 
• 96794-64-8 2,5-Dimethyl-phenyl-vinylborinsaeure-butylester 
• 18870-13-8 2,5-dicyanobromobenzene 
• 93723-10-5 (2,5-Dimethyl-phenyl)-(4-dimethylamino-phenyl)-methanol 

Relevant articles and documents

Triptycenyl Sulfide: A Practical and Active Catalyst for Electrophilic Aromatic Halogenation Using N-Halosuccinimides

A Lewis base catalyst Trip-SMe (Trip = triptycenyl) for electrophilic aromatic halogenation using N-halosuccinimides (NXS) is introduced. In the presence of an appropriate activator (as a noncoordinating-anion source), a series of unactivated aromatic compounds were halogenated at ambient temperature using NXS. This catalytic system was applicable to transformations that are currently unachievable except for the use of Br2 or Cl2: e.g., multihalogenation of naphthalene, regioselective bromination of BINOL, etc. Controlled experiments revealed that the triptycenyl substituent exerts a crucial role for the catalytic activity, and kinetic experiments implied the occurrence of a sulfonium salt [Trip-S(Me)Br][SbF6] as an active species. Compared to simple dialkyl sulfides, Trip-SMe exhibited a significant charge-separated ion pair character within the halonium complex whose structural information was obtained by the single-crystal X-ray analysis. A preliminary computational study disclosed that the πsystem of the triptycenyl functionality is a key motif to consolidate the enhancement of electrophilicity.

Molecular tweezers based on trivalent phosphine, preparation method of molecular tweezers, metal-molecular tweezers catalyst, and preparation method and application of metal-molecular tweezers catalyst

The invention relates to the technical field of inorganic-metal organic crossing and relates to the technical field of molecular tweezers, in particular to molecular tweezers based on trivalent phosphine, a preparation method of the molecular tweezers, a metal-molecular tweezer catalyst, a preparation method of the metal-molecular tweezer catalyst and an application of the metal-molecular tweezercatalyst, the molecular tweezer based on trivalent phosphine is named as P-MV-PCN-521-R, and R is any one of benzoic acid, p-nitrobenzoic acid, formic acid, p-methylbenzoic acid and dichloroacetic acid. The molecular tweezers based on the trivalent phosphine have distance adjustability. The trivalent phosphine-based metal-molecular tweezer catalyst provided by the invention has a high crystallinesurface area and a high specific surface area. The trivalent phosphine-based metal-molecular tweezer catalyst has good chemical stability and thermal stability, and is a primary condition for applyingthe trivalent phosphine-based metal-molecular tweezer catalyst to the actual field. The trivalent phosphine-based metal-molecular tweezer catalyst with adjustable distance provided by the invention has good selectivity for bromination of aromatic compounds.

Regioselective monobromination of aromatics via a halogen bond acceptor-donor interaction of catalytic thioamide and N-bromosuccinimide

Regioselective monobromination of various aromatics was achieved at room temperature using N-bromosuccinimide and 5 mol% of thioamides in acetonitrile. With thiourea as catalyst, activated aromatics, such as anisole, acetanilide, benzamide and phenol analogues containing electron donating or withdrawing groups, were brominated with high regioselectivity. Room temperature brominations of weakly activated aromatics and deactivated 9-fluorenone were accomplished by 5 mol% thioacetamide, higher substrates concentrations and longer reaction times. A backbonding of the bromine lone pairs with the π*of C[dbnd]S group and a halogen bond between the halogen bond donor bromine and the halogen bond acceptor sulfur of the thioamide are thought to be the principal interactions and cause of N-bromosuccinimide activation.