15045-43-9

Basic information

• Product Name: 2,2,5,5-TETRAMETHYLTETRAHYDROFURAN
• Synonyms: TETRAHYDRO-2,2,5,5-TETRA-METHYLFURAN;2,2,5,5-TETRAMETHYLTETRAHYDROFURAN;2 2 5 5-TETRAMETHYLTETRAHYDROFURAN 97%;2,2,5,5-Tetramethyltetrahydrofurane;2,2,5,5-Tetramethyltetrahydrofuran,98%;Furan, tetrahydro-2,2,5,5-tetraMethyl-
• CAS NO: 15045-43-9
• Molecular Formula: C₈H₁₆O
• Molecular Weight: 128.21
• EINECS: 239-117-9
• Mol File: 15045-43-9.mol
• Article Data: 13

Chemical Properties

• Boiling Point: 112 °C(lit.)
• Flash Point: 39 °F
• Appearance: clear colourless liquid
• Density: 0.811 g/mL at 25 °C(lit.)
• Vapor Pressure: 26.1mmHg at 25°C
• Refractive Index: n20/D 1.405(lit.)
• BRN: 103074
• CAS DataBase Reference: 2,2,5,5-TETRAMETHYLTETRAHYDROFURAN(CAS DataBase Reference)
• NIST Chemistry Reference: 2,2,5,5-TETRAMETHYLTETRAHYDROFURAN(15045-43-9)
• EPA Substance Registry System: 2,2,5,5-TETRAMETHYLTETRAHYDROFURAN(15045-43-9)

Safety Data

• Hazard Codes: F
• Statements: 11
• Safety Statements: 16-29-33
• RIDADR: UN 1993 3/PG 2
• WGK Germany: 3
• HazardClass: 3
• PackingGroup: II
• Hazardous Substances Data: 15045-43-9(Hazardous Substances Data)

Usage

Chemical Properties

CLEAR COLOURLESS LIQUID

InChI:InChI=1/C8H16O/c1-7(2)5-6-8(3,4)9-7/h5-6H2,1-4H3

Synthetic route

2,5-dimethyl-2,5-hexanediol (110-03-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
With beta-zeolite HCZB 25 at 0.85 - 105℃; for 1.5h; Reagent/catalyst;	100%
Nafion-H at 130℃; for 2h;	94%
With penthaethoxyphosphorane In dichloromethane for 450h; Ambient temperature;	79.1%

2,5-dimethyl-2,5-hexanediol (110-03-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 2,5-dimethyl-4-hexen-2-ol (14908-27-1)

Conditions	Yield
With chloro-trimethyl-silane; dimethyl sulfoxide In benzene at 20℃; for 75h;	A 75% B 21%

3-Phenyl-1-propanol (122-97-4) + 2-diethylamino-4,4,7,7-tetramethyl-1,3,2-dioxaphosphepane (261920-18-7) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + bis(3-phenylpropyl) hydrophosphonate + 4,4,7,7-tetramethyl-2-oxo-2-(3-phenylpropyloxy)-1,3,2-dioxaphosphepane

Conditions	Yield
Stage #1: 3-Phenyl-1-propanol; 2-diethylamino-4,4,7,7-tetramethyl-1,3,2-dioxaphosphepane With 1H-tetrazole In dichloromethane at 20℃; for 22h; Substitution; Stage #2: With 3-chloro-benzenecarboperoxoic acid at -78 - 20℃; for 0.5h; Oxidation;	A 36% B 63% C 4%

formaldehyd (50-00-0) + 2,5-dimethyl-2,5-hexanediol (110-03-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 4,4,7,7-tetramethyl-1,3-dioxepane (77661-71-3)

Conditions	Yield
With N-Phenyl-2-naphthylamine; toluene-4-sulfonic acid

2,5-dimethyl-2,5-hexanediol (110-03-2) + aniline hydrobromide (542-11-0) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 2,5-Dimethyl-2,4-hexadiene (764-13-6)

Conditions	Yield
beim Destillieren;

2,5-dimethyl-1,5-hexadiene (627-58-7) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
With sulfuric acid at 6℃; im geschlossenen Rohr;

2,5-Dimethyl-2,4-hexadiene (764-13-6) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
With sulfuric acid at 6℃; im geschlossenen Rohr;

2,5-dibromo-2,5-dimethyl-hexane (54462-71-4) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
With potassium carbonate

5-bromo-2,5-dimethyl-hexan-2-ol (855914-39-5) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 2,5-dibromo-2,5-dimethyl-hexane (54462-71-4)

Conditions	Yield
Erhitzen ueber den Schmelzpunkt;

2,5-dimethyl-4-hexen-2-ol (14908-27-1) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
With sulfuric acid

formaldehyd (50-00-0) + 2,5-dimethyl-2,5-hexanediol (110-03-2) + N-Phenyl-2-naphthylamine (135-88-6) + toluene-4-sulfonic acid (104-15-4) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 4,4,7,7-tetramethyl-1,3-dioxepane (77661-71-3)

2,5-dimethyl-2,5-hexanediol (110-03-2) + phosphoric acid (86119-84-8, 7664-38-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
at 140℃;

2,5-dimethyl-hex-3-ene-2,5-diol (23359-01-5) + sulfuric acid (7664-93-9) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
higher-melting 2.5-dimethyl-hexene-(3)-diol-(2.5);

2,5-dimethyl-4-hexen-2-ol (14908-27-1) + sulfuric acid (7664-93-9) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

2,5-dimethyl-hex-3-ene-2,5-diol (23359-01-5) + iodine (7553-56-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
die Reaktion verlaeuft bei der α-Form rascher als bei der β-Form; higher-melting 2.5-dimethyl-hexene-(3)-diol-(2.5);
die Reaktion verlaeuft bei der α-Form rascher als bei der β-Form; lower-melting 2.5-dimethyl-hexene-(3)-diol-(2.5);

(Z)-2,5-dimethylhex-3-ene-2,5-diol (6117-86-8) + acid → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

2,5-dimethyl-hex-3-ene-2,5-diol (23359-01-5) + KHSO4 → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
at 140 - 160℃; higher-melting 2.5-dimethyl-hexene-(3)-diol-(2.5);

(Z)-2,5-dimethylhex-3-ene-2,5-diol (6117-86-8) + hydrogen bromide (10035-10-6, 12258-64-9) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 2,5-dibromo-2,5-dimethyl-hex-3-ene (90154-62-4)

Conditions	Yield
at 25℃;

4-oxopentanoic acid ethyl ester (539-88-8) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
Multi-step reaction with 2 steps 2: diluted sulfuric acid View Scheme

5-bromo-2,5-dimethyl-hexan-2-ol (855914-39-5) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9)

Conditions	Yield
Multi-step reaction with 2 steps 1: Erhitzen ueber den Schmelzpunkt 2: potassium carbonate solution View Scheme

2,5-dimethyl-2,5-hexanediol (110-03-2) → 2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 2,5-dimethyl-1,5-hexadiene (627-58-7) + 2,5-Dimethyl-2,4-hexadiene (764-13-6) + 2,5-dimethyl-4-hexen-2-ol (14908-27-1) + 2,5-dimethyl-1,4-hexadiene (927-97-9)

Conditions	Yield
With H-BEA zeolite In melt at 110℃; for 2h; Catalytic behavior; Reagent/catalyst;

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + methylenebis(diphenylphosphane)-borane(1:2) (24442-15-7) + dimethylsulfide borane complex (13292-87-0) → Li{H3BCH(PPh2BH3)2}(2,2,5,5-tetramethyltetrahydrofuran)

Conditions	Yield
Stage #1: methylenebis(diphenylphosphane)-borane(1:2) With n-butyllithium In hexane; toluene at 20℃; for 0.0833333h; Inert atmosphere; Schlenk technique; Stage #2: dimethylsulfide borane complex In hexane; toluene Inert atmosphere; Schlenk technique; Stage #3: 2,2,5,5-tetramethyltetrahydrofuran In hexane; toluene at -20℃; Inert atmosphere; Schlenk technique;	83.9%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + C12H36K2N2Si4 → [(2,2,5,5-tetramethyltetrahydrofuran)K(hexamethyldisilazane)]2

Conditions	Yield
In pentane Inert atmosphere; Schlenk technique;	82%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + calcium bis[bis(trimethylsilyl)amide] dimer (131298-03-8) → C20H52CaN2OSi4

Conditions	Yield
In pentane at -20℃; for 24h; Schlenk technique; Inert atmosphere;	82%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + strontium bis[bis(trimethylsilyl)amide] → C20H52N2OSi4Sr

Conditions	Yield
In pentane at -20℃; for 24h; Schlenk technique; Inert atmosphere;	75%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + [(HC{(Me)CN-2,6-i-Pr2C6H3}2)CaH]2 + hexaphenylditin (1064-10-4) → C55H72CaN2OSn

Conditions	Yield
In benzene-d6 at 20℃; for 48h; Inert atmosphere;	75%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + methylenebis(diphenylphosphane)-borane(1:2) (24442-15-7) → Li{CH(PPh2BH3)2}(2,2,5,5-tetramethyltetrahydrofuran)

Conditions	Yield
Stage #1: methylenebis(diphenylphosphane)-borane(1:2) With n-butyllithium In hexane; toluene at 20℃; Inert atmosphere; Schlenk technique; Stage #2: 2,2,5,5-tetramethyltetrahydrofuran In toluene at 80℃; for 18h; Inert atmosphere; Schlenk technique;	72%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + N-Isopropylaniline (768-52-5) + dibutylmagnesium (1191-47-5) → C26H40MgN2O

Conditions	Yield
In pentane at 0 - 20℃; Inert atmosphere; Schlenk technique;	71.5%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + [(HC{(Me)CN-2,6-i-Pr2C6H3}2)CaH]2 + triphenylstannane (892-20-6) → C55H72CaN2OSn

Conditions	Yield
In toluene at 20℃; Inert atmosphere;	68%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + C24H72Ba2N4Si8 → C20H52BaN2OSi4

Conditions	Yield
In pentane at -20℃; for 24h; Schlenk technique; Inert atmosphere;	66%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + 1,1,1,3,3,3-hexamethyl-disilazane (999-97-3) → [LiN(SiMe3)2]4*(2,2,5,5-tetramethyltetrahydrofuran)

Conditions	Yield
Stage #1: 1,1,1,3,3,3-hexamethyl-disilazane With n-butyllithium In hexane at -78℃; Inert atmosphere; Schlenk technique; Stage #2: 2,2,5,5-tetramethyltetrahydrofuran In hexane at -40℃; Inert atmosphere; Schlenk technique;	65%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + C18H54N3Na3Si6 → [(2,2,5,5-tetramethyltetrahydrofuran)Na(hexamethyldisilazane)]2

Conditions	Yield
In pentane Inert atmosphere; Schlenk technique;	58%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + ((((CH3)3Si)2N)Mg(μ-N(Si(CH3)3)2))2 (141997-73-1) → C20H52MgN2OSi4

Conditions	Yield
In pentane at -20℃; for 24h; Schlenk technique; Inert atmosphere;	58%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + [(HC{(Me)CN-2,6-i-Pr2C6H3}2)CaH]2 + triphenylstannane (892-20-6) + diisopropyl-carbodiimide (693-13-0) → C62H86CaN4OSn

Conditions	Yield
Stage #1: 2,2,5,5-tetramethyltetrahydrofuran; [(HC{(Me)CN-2,6-i-Pr2C6H3}2)CaH]2; triphenylstannane In benzene-d6 at 20℃; for 16h; Inert atmosphere; Stage #2: diisopropyl-carbodiimide In benzene-d6 at 20℃; for 2h; Inert atmosphere;	56%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + [Rb(hexamethyldisilazane)]2 → [(2,2,5,5-tetramethyltetrahydrofuran)Rb(hexamethyldisilazane)]2

Conditions	Yield
In pentane Inert atmosphere; Schlenk technique;	50%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) → perfluoro(2,2,5-trimethyltetrahydrofuran) (110719-88-5) + 3-hydropentadecafluoro-2,2,5,5-tetramethyltetrahydrofuran (110743-66-3) + perfluoro(2,2,5,5-tetramethyltetrahydrofuran) (110719-86-3) + perfluoro(2,2,5-trimethyltetrahydropyran) (110719-87-4)

Conditions	Yield
With fluorine at -120 - 20℃; for 336h; Yield given;	A n/a B n/a C 45% D n/a
With fluorine at -120 - 20℃; for 336h; Yields of byproduct given;	A n/a B n/a C 45% D n/a
With fluorine at -120 - 20℃; for 336h; Yield given. Yields of byproduct given;

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + C12H36Cs2N2Si4 → [(2,2,5,5-tetramethyltetrahydrofuran)Cs(hexamethyldisilazane)]2

Conditions	Yield
In pentane Inert atmosphere; Schlenk technique;	25%

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) + phenol (108-95-2) → 5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-ol (22824-31-3)

Conditions	Yield
With aluminium trichloride; Petroleum ether
With hydrogenchloride; aluminium trichloride In n-heptane
With aluminium trichloride; Petroleum ether

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) → 2,5-dichloro-2,5-dimethyl hexane (6223-78-5)

Conditions	Yield
With hydrogenchloride

2,2,5,5-tetramethyltetrahydrofuran (15045-43-9) → para-xylene (106-42-3)

Conditions	Yield
With hydrogen at 510℃; Leiten ueber Aluminiumoxid-Chromoxid-Magnesiumoxid;

Upstream product

• 50-00-0 formaldehyd 
• 110-03-2 2,5-dimethyl-2,5-hexanediol 
• 542-11-0 aniline hydrobromide 
• 627-58-7 2,5-dimethyl-1,5-hexadiene 
• 764-13-6 2,5-Dimethyl-2,4-hexadiene 
• 54462-71-4 2,5-dibromo-2,5-dimethyl-hexane 
• 855914-39-5 5-bromo-2,5-dimethyl-hexan-2-ol 
• 14908-27-1 2,5-dimethyl-4-hexen-2-ol 
• 135-88-6 N-Phenyl-2-naphthylamine 
• 104-15-4 toluene-4-sulfonic acid 
• 86119-84-8 phosphoric acid 
• 23359-01-5 2,5-dimethyl-hex-3-ene-2,5-diol 
• 7664-93-9 sulfuric acid 
• 7553-56-2 iodine 

Downstream Products

• 22824-31-3 5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-ol 
• 6223-78-5 2,5-dichloro-2,5-dimethyl hexane 
• 106-42-3 para-xylene 
• 76528-08-0 5-Benzyl-4-isopropylidene-2,2-dimethyl-3,4-dihydro-2H-pyrrole 
• 76527-93-0 tetrahydrobenzindol 
• 627-58-7 2,5-dimethyl-1,5-hexadiene 
• 764-13-6 2,5-Dimethyl-2,4-hexadiene 
• 927-97-9 2,5-dimethyl-1,4-hexadiene 
• 74-84-0 ethane 
• 676-49-3 Monodeuteromethan 
• 513-35-9 2-methyl-but-2-ene 
• 34557-54-5 methane 
• 1630-94-0 1,1-dimethylcyclopropane 
• 67-64-1 acetone 

Relevant articles and documents

Straightforward synthesis of rubidium bis(trimethylsilyl)amide and complexes of the alkali metal bis(trimethylsilyl)amides with weakly coordinating 2,2,5,5-tetramethyltetrahydrofuran

Rubidium bis(trimethylsilyl)amide (rubidium hexamethyldisilazanide, Rb(hmds)) is accessible on a large scale with excellent yields via a magnetite-catalyzed metalation of hexamethyldisilazane (H(hmds)) in liquid ammonia. Recrystallization of solvent-free alkali metal hexamethyldisilazanides [A(hmds)]n of sodium to cesium from solutions containing 2,2,5,5-tetramethyltetrahydrofuran (Me4THF, thf?) yields the dinuclear complexes [(thf?)A(hmds)]2, which show a rather asymmetric coordination behavior of the bulky ether ligand with strongly bent A-A-O moieties for the heavier K, Rb, and Cs congeners, whereas in the Na complex, the ether ligand is clamped between the trimethylsilyl groups. In hydrocarbon solutions, dissociation of these compounds is observed leading to the liberation of this bulky and weakly binding cyclic ether.

PREPARATION OF TMTHF

The invention relates to a process for the preparation of 2,2,5,5- tetramethyltetrahydrofuran (TMTHF) comprising contacting a TMTHF precursor with a solid catalyst, wherein the TMTHF precursor is 2,5-dimethylhexane-2,5-dioland/or 2,5-dimethyl-4- hexen-2-ol,and wherein the solid catalyst is a beta zeolite. It also relates to the use of a beta zeolite catalyst for this process. It also relates to the use of the TMTHF produced by the process of the invention as solvent.

Cyclization of alkanediols in high-temperature liquid water with high-pressure carbon dioxide

Dehydration of 1,4-butanediol (1,4-BDO) to tetrahydrofuran (THF), 2R,5R-hexanediol (2R,5R-HDO) to 2,5-dimethyltetrahydrofuran (2,5-DMTHF), and 2,5-dimethyl-2,5-hexanediol (2,5-DM-2,5-HDO) to 2,2,5,5- tetramethyltetrahydrofuran (2,2,5,5-TMTHF) proceeded in high-temperature liquid water at 523 K. The formation rates of cyclic ethers were enhanced by high-pressure carbon dioxide (16.2 MPa). The order of dehydration rates in high-temperature water with carbon dioxide was 2,5-DM-2,5-HDO > 2R,5R-HDO > 1,4-BDO (tertiary > secondary > primary alcohols), which was the same order as the stability of corresponding carbocation species.