294-93-9

Basic information

• Product Name: 12-Crown-4
• Synonyms: Eoct;Ethylene oxide cyclic tetramer;1,4,7,10-TETRAOXYCYCLODODECANE;1,4,7,10-TETRAOXACYCLODODECANE;12-CROWN 4-ETHER;12-CROWN-4;LITHIUM IONOPHORE V;CROWN ETHER/12-CROWN-4
• CAS NO: 294-93-9
• Molecular Formula: C₈H₁₆O₄
• Molecular Weight: 176.21
• EINECS: 206-036-5
• Product Categories: Crown Ethers;Functional Materials;Macrocycles for Host-Guest Chemistry
• Mol File: 294-93-9.mol
• Article Data: 13

Chemical Properties

• Melting Point: 16 °C(lit.)
• Boiling Point: 61-70 °C0.5 mm Hg(lit.)
• Flash Point: >230 °F
• Appearance: Clear colorless to slightly yellow/Liquid After Melting
• Density: 1.089 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.0269mmHg at 25°C
• Refractive Index: n20/D 1.463(lit.)
• Storage Temp.: 2-8°C
• Water Solubility: MISCIBLE
• Sensitive: Air Sensitive
• BRN: 1363064
• CAS DataBase Reference: 12-Crown-4(CAS DataBase Reference)
• NIST Chemistry Reference: 12-Crown-4(294-93-9)
• EPA Substance Registry System: 12-Crown-4(294-93-9)

Safety Data

• Hazard Codes: T+,Xn,Xi
• Statements: 26-36/37/38-20/21/22
• Safety Statements: 28-36/37-45-36-26
• RIDADR: UN 2810
• WGK Germany: 3
• RTECS: XF0550000
• F: 3-9-23
• TSCA: Yes
• HazardClass: 6.1
• PackingGroup: III
• Hazardous Substances Data: 294-93-9(Hazardous Substances Data)

Usage

Synthesis Reference(s)

Tetrahedron Letters, 15, p. 4029, 1974 DOI: 10.1016/S0040-4039(01)92075-1

Purification Methods

The distilled crude product has to be recrystallised from pentane at -20o to remove acyclic material. It is then dried over P2O5. It complexes Li. [Anet et al. Acta Chem Scand 27 3395 1973, Beilstein 19/11 V 334.]

InChI:InChI=1/C8H16O4/c1-2-10-5-6-12-8-7-11-4-3-9-1/h1-8H2

Synthetic route

[Li(12-crown-4)][W(CO)5(P(CH(SiMe3)2)(OPh))] + phenylacetylene (536-74-3) + methyl trifluoromethanesulfonate (333-27-7) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + [W(CO)5(P(CHCMePh)(CH(SiMe3)2)(OPh))] (1416967-44-6)

Conditions

Yield

In tetrahydrofuran byproducts: LiOTf; under Ar, soln. of phenylacetylene (1.0 mmol) added to W complex in THF at -78°C, after 0.5 h of stirring, phenylacetylene added, mixt. heated at reflux for 2 h, cooled to ambient temp., MeOTf added; volatiles evapd. in vac. (ca. 0.01 mbar), raw product purified by columnchromy. (SiO2, -20°C, petroleum ether/Et2O, 10:1), product obtai ned from 2nd fraction, detd. by 1H NMR, 13C NMR, 31P NMR, 29Si NMR, IR, MS;

A n/a B 62%

ethylene glycol (107-21-1) + 1,2-bis(2-chloroethoxy)ethane (112-26-5) → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
With potassium hydroxide for 0.1h; microwave irradiation;	37%

Tetraethylene glycol (112-60-7) → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
With cyanomethylenetributyl-phosphorane In benzene at 60℃; sealed vessel;	30%
With p-toluenesulfonyl chloride; lithium tert-butoxide In tert-butyl alcohol Heating;	27%

3-oxa-1,5-dichloropentane (111-44-4) + diethylene glycol (111-46-6) → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
With lithium hydride In dimethyl sulfoxide Heating; different basis as 'template' agents, other solvents;	24%
With lithium hydride In dimethyl sulfoxide Heating;	24%

Tetraethylene glycol (112-60-7) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + 24-crown-8 (33089-37-1) + <36>crown-12 (71092-59-6) + 48-Crown-16 (71092-61-0)

Conditions	Yield
With potassium hydroxide; p-toluenesulfonyl chloride In 1,4-dioxane at 65℃; Further byproducts given;	A 1.4% B 23% C 11% D 4.3%

Tetraethylene glycol (112-60-7) + diethylene glycol (111-46-6) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + 18-crown-6 ether (17455-13-9) + 24-crown-8 (33089-37-1)

Conditions	Yield
With potassium hydroxide; p-toluenesulfonyl chloride In 1,4-dioxane at 60℃;	A n/a B 23% C 3%

Tetraethylene glycol (112-60-7) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + 24-crown-8 (33089-37-1)

Conditions	Yield
With sodium hydroxide; p-toluenesulfonyl chloride In 1,4-dioxane at 20℃;	A 3% B 12%

C8H16O4*K(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
In methanol at 25℃; Equilibrium constant; enthalpy-entropy compensation for the complexation reactions of crown ethers with alkaline cations;

2C8H16O4*K(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + C8H16O4*K(1+)

Conditions	Yield
In methanol at 25℃; Equilibrium constant; enthalpy-entropy compensation for the complexation reactions of crown ethers with alkaline cations;

C8H16O4*C3H9N*H(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + trimethylammonium (145384-53-8)

Conditions	Yield
Thermodynamic data; enthalpy and entropy changes for the complex dissociation reaction: ΔH0D, ΔS0D;

C8H16O4*C6H13N*H(1+) → cyclohexyl-ammonium cation (29384-28-9) + (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
Thermodynamic data; enthalpy and entropy changes for the complex dissociation reaction: ΔH0D, ΔS0D;

C8H16O4*C5H5N*H(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + pyridin-1-ium (16969-45-2)

Conditions	Yield
Thermodynamic data; enthalpy and entropy changes for the complex dissociation reaction: ΔH0D, ΔS0D;

C8H16O4*C4H4N2*H(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9) + 1,2-diazineH+ (17009-97-1)

Conditions	Yield
Thermodynamic data; enthalpy and entropy changes for the complex dissociation reaction: ΔH0D, ΔS0D;

12-Crown-4 lithium perchlorate → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
In acetone Equilibrium constant; various solvents (MeNO2, MeCN, propylene carbonate, MeOH, pyridine), complex formation between crown ethers and lithim ion, effect of solvent of the stability of complexes, 7Li NMR study;

C8H16O4*2ClO4(1-)*2Li(1+) → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
In nitromethane Equilibrium constant; various solvents (MeCN, propylene carbonate, Me2CO, MeOH, pyridine), complex formation between crown ethers and lithim ion, effect of solvent of the stability of complexes, formation of 1:1 and 1:2 complexes, 7Li NMR study;

1,4,7,10-Tetraoxa-cyclododecane; compound with GENERIC INORGANIC NEUTRAL COMPONENT → (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
With Iodine monochloride In benzene at 24.9℃; Equilibrium constant;

C8H16O4*C10H15(1-)*C24BF20(1-)*Si(2+) → 1,4-dioxane (123-91-1) + (1,4,7,10-tetraoxacyclododecane) (294-93-9)

Conditions	Yield
In dichloromethane-d2 for 480h;

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + Lu(N(SiMe3)2)3 + sodium trimethylsilanolate (18027-10-6) → [Na((CH2CH2O)4)2](1+)*[Lu(N(Si(CH3)3)2)3(OSi(CH3)3)](1-)=[Na((CH2CH2O)4)2][Lu(N(Si(CH3)3)2)3(OSi(CH3)3)]

Conditions	Yield
In hexane dry atm.; molar ratio 1:1:2, stirring (room temp., 6 h); filtn., washing (n-hexane), drying (vac.); elem. anal.;	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + sodium trimethylsilanolate (18027-10-6) + tris(bis(trimethylsilyl)amido)europium(III) → [Na((CH2CH2O)4)2](1+)*[Eu(N(Si(CH3)3)2)3(OSi(CH3)3)](1-)=[Na((CH2CH2O)4)2][Eu(N(Si(CH3)3)2)3(OSi(CH3)3)]

Conditions	Yield
In hexane dry atm.; molar ratio 1:1:2, stirring (room temp., 6 h); filtn., washing (n-hexane), drying (vac.); elem. anal.;	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + tris(bis(trimethylsilyl)amido)ytterbium(III) + sodium trimethylsilanolate (18027-10-6) → [Na((CH2CH2O)4)2](1+)*[Yb(N(Si(CH3)3)2)3(OSi(CH3)3)](1-)=[Na((CH2CH2O)4)2][Yb(N(Si(CH3)3)2)3(OSi(CH3)3)]

Conditions	Yield
In hexane dry atm.; molar ratio 1:1:2, stirring (room temp., 6 h); filtn., washing (n-hexane), drying (vac.); elem. anal.;	100%

tris(bis(trimethylsilyl)amido)samarium(III) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) + sodium trimethylsilanolate (18027-10-6) → [Na((CH2CH2O)4)2](1+)*[Sm(N(Si(CH3)3)2)3(OSi(CH3)3)](1-)=[Na((CH2CH2O)4)2][Sm(N(Si(CH3)3)2)3(OSi(CH3)3)]

Conditions	Yield
In hexane dry atm.; molar ratio 1:1:2, stirring (room temp., 6 h); filtn., washing (n-hexane), drying (vac.); elem. anal.;	100%

tetrahydrofuran (109-99-9) + n-butyllithium (109-72-8, 29786-93-4) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) + C12H20B10 → C12H19B10(1-)*Li(1+)*2C4H8O*2C8H16O4

Conditions	Yield
Stage #1: tetrahydrofuran; n-butyllithium; C12H20B10 Stage #2: (1,4,7,10-tetraoxacyclododecane) In tetrahydrofuran	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + [Li(THF)3][UO2(N(SiHMe2)tBu)3] → [Li(12-crown-4)2][UO2(N(SiHMe2)tBu)3]

Conditions	Yield
In tetrahydrofuran for 1h;	100%

beryllium(II) chloride (7787-47-5) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) → [(BeCl)([12]crown-4)]Cl

Conditions	Yield
In dichloromethane at 20℃; Inert atmosphere; Schlenk technique;	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + C36H30Be3 + phenyllithium (591-51-5) → C16H32Li2O8(2+)*2C18H15Be(1-)

Conditions	Yield
Stage #1: (1,4,7,10-tetraoxacyclododecane); C36H30Be3; phenyllithium In benzene-d6 Stage #2: In benzene-d6 at 80℃;	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + C36H30Be3 → C14H21BeO4(1+)*C18H15Be(1-)

Conditions	Yield
Stage #1: (1,4,7,10-tetraoxacyclododecane); C36H30Be3 In benzene-d6 Stage #2: In benzene-d6 Heating;	100%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + {Na}{(4,5-bis(diisopropylphosphino)-2,7,9,9-tetramethyl-9H-acridin-10-ide)Ni(CO)} → {Na(12-crown-4)2}{(4,5-bis(diisopropylphosphino)-2,7,9,9-tetramethyl-9H-acridin-10-ide)Ni(CO)}

Conditions	Yield
In tetrahydrofuran at 20℃; for 0.5h; Inert atmosphere;	99%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + [W(carbonyl)5([bis(trimethylsilyl)methyl]cyanophosphane)] (851576-85-7) + tert.-butyl lithium (594-19-4) → [(OC)5WP(CH(SiMe3)2)CNLi(12-crown-4)] (947333-61-1)

Conditions	Yield
In diethyl ether; hexane under Ar; soln. of t-BuLi in n-hexane added dropwise at -80°C to stirred soln. of W complex in Et2O and 12-crown-4; warmed slowly to roomtemp. for 3.5 h; solvent removed under vac.; washed with Et2O and n-pentane; dried under reduced pressure; elem. anal.;	98.3%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + (Si(o-C6H4PiPr2)3)Fe[(CO)Na(THF)3] (1277179-18-6) → [(Na(12-crown-4)2][(Si(o-C6H4PiPr2)3)Fe(CO)]

Conditions	Yield
In tetrahydrofuran (Schlenk or glovebox, N2) the soln. of 12-crown-4 in THF was added dropwise to a soln. of complex in THF, stirred for 30 min at room temp.; filtered, volatiles were removed under vac., the solid was washed with pentane; elem. anal.;	98%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + (4,5-bis(diisopropylphosphino)-2,7,9,9-tetramethyl-9H-acridin-10-ide)Ni-μ-CO2-Na*THF → {Na(12-crown-4)2}{(4,5-bis(diisopropylphosphino)-2,7,9,9-tetramethyl-9H-acridin-10-ide)Ni(CO2)}

Conditions	Yield
In tetrahydrofuran at 20℃; for 0.5h; Inert atmosphere;	98%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + C42H51CrLi2O3 → C30H25Cr(2-)*2C12H24LiO5(1+)

Conditions	Yield
In tetrahydrofuran at 0℃; Solvent; Inert atmosphere; Schlenk technique;	98%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + [Na(tetrahydrofuran)x][(Mo(N[i-Pr](3,5-C6H3Me2)3)2N] + nitrogen (7727-37-9) → [Mo(N[i-Pr](3,5-C6H3Me2)3N] (394246-98-1) + [Na(12-crown-4)2][(Mo(N[i-Pr](3,5-C6H3Me2)3)N2]

Conditions	Yield
In not given at 25°C? 1 atm and in the presence of crown ether (2 equiv. per Na);	A n/a B 97%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + C24H48LiP2Si4(1-)*4C4H8O*Li(1+) → C12H24PSi2(1-)*2C8H16O4*Li(1+)

Conditions	Yield
In tetrahydrofuran at 20℃; for 3h; Inert atmosphere; Glovebox;	97%

tin(II) trifluoromethanesulfonate + (1,4,7,10-tetraoxacyclododecane) (294-93-9) → bis([12]crown-4)tin(II) triflate

Conditions	Yield
In tetrahydrofuran standard inert-atmosphere techniques; soln. of (12)crown-4 (0.943 mmol) added to soln. of Sn(OTf)2 (0.479 mmol), stiired for 2 h; solvent removed (in vac.), washed with pentane; elem. anal.;	96%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + Ba((N,N-dimethylamino)diboranato)2(diethyl ether)(x) → bis[(N,N-dimethylamino)diboranato](12-crown-4) barium(II)

Conditions	Yield
In diethyl ether under Ar atm. using Schlenk techniques; to soln. of Ba complex in Et2O was added Lewis base; mixt. stirred overnight; solid filtered; washed (pentane); dried under vac.; elem. anal.;	96%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + potassium hexamethylsilazane (40949-94-8) → C28H68K2N2O8Si4

Conditions	Yield
In toluene Inert atmosphere; Schlenk technique;	96%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + C36H54FeGaN2P3(1-)*C12H24NaO3(1+) → C36H54FeGaN2P3(1-)*C16H32NaO8(1+)

Conditions	Yield
In tetrahydrofuran at 20℃; for 2h;	96%

triphenylboroxine (3262-89-3) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) + water (7732-18-5) + lithium pyrazolide → Li[Li(tetrahydrofuran)(phenyl(pyrazolyl)B(μ-O)(μ-OB(phenyl)O)B(pyrazolyl)phenyl)]*(12-crown-4)*2H2O

Conditions	Yield
In tetrahydrofuran (N2); using Schlenk techniques; stirring of mixt. of Li(pz) (2 equiv.), Ph3B3O3 (1 equiv.) and 12-crown-4 (2 equiv.) in THF at room temp. for 30min; addn. of hexane; cooling to -5°C overnight; crystn.; rinsing withhexane; drying under reduced pressure;	95%

tetrahydrofuran (109-99-9) + triphenylboroxine (3262-89-3) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) + lithium pyrazolide → C8H16LiO4(1+)*C28H29B3LiN4O4(1-)

Conditions	Yield
for 0.5h;	95%

selenium (7782-49-2) + (1,4,7,10-tetraoxacyclododecane) (294-93-9) + C44H69ClLiLuO3Si2 + pivalaldehyde (630-19-3) → C37H53ClLuOSeSi2(1-)*Li(1+)*2C8H16O4

Conditions	Yield
Stage #1: C44H69ClLiLuO3Si2; pivalaldehyde In tetrahydrofuran at 20℃; for 3h; Inert atmosphere; Stage #2: selenium In tetrahydrofuran Inert atmosphere; Stage #3: (1,4,7,10-tetraoxacyclododecane) In tetrahydrofuran for 1h; Inert atmosphere;	95%

(1,4,7,10-tetraoxacyclododecane) (294-93-9) + uranium(III) tris(1,3-bis-(trimethylsilyl)cyclopentadienyl) (174090-55-2) + sodium (7440-23-5) → [Na(12-crown-4)2][(C5H3(SiMe3)2)3U]

Conditions	Yield
In tetrahydrofuran for 0.5h; Glovebox; Inert atmosphere; Schlenk technique;	95%

Upstream product

• 112-60-7 Tetraethylene glycol 
• 111-46-6 diethylene glycol 
• 929-72-6 2-(2-(2-(vinyloxy)ethoxy)ethoxy)ethanol 
• 536-74-3 phenylacetylene 
• 333-27-7 methyl trifluoromethanesulfonate 
• 107-21-1 ethylene glycol 
• 112-26-5 1,2-bis(2-chloroethoxy)ethane 
• 111-44-4 3-oxa-1,5-dichloropentane 

Downstream Products

• 95189-83-6 C₁₉H₁₅Li*2C₈H₁₆O₄*C₄H₈O 
• 5587-62-2 dimethylsilyl diisocyanate 
• 866922-55-6 [Y(CH₂SiMe₃)2([12]-crown-4)(tetrahydrofuran)][B(CH₂SiMe₃)(C₆F₅)3] complex 
• 447457-64-9 [Y(CH₂SiMe₃)2([12]-crown-4)(tetrahydrofuran)][B(CH₂SiMe₃)Ph₃] complex 
• 615564-57-3 [1-(Ph₂N)-2-(B(H)(C₆F₅)2)C₆H₄][Li(12-crown-4)] 
• 671802-46-3 [Y(CH₂SiMe₃)2(12-crown-4)][BPh₄] 
• 881995-06-8 [Lu(tri(tert-butoxy)silanolato)(trimethylsilylmethyl)(12-crown-4)(thf)][BPh₄] 

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Formation of heterocycles by the Mitsunobu reaction. Stereoselective ynthesis of (+)-α-skytanthine

Cyanomethylenetributylphosphorane was shown to mediate the dehydrocyclization of diols and amino alcohols to give the corresponding 6-membered O- and N-heterocycles in 90% or better yields. Using the reaction as a key step, (+)-α-skytanthine, a unique mono terpene alkaloid, was synthesized stereoselectively.

TEMPLATE EFFECTS. 7. LARGE UNSUBSTITUTED CROWN ETHERS FROM POLYETHYLENE GLYCOLS: FORMATION, ANALYSIS, AND PURIFICATION

Through the reaction of polyethylene glycols with tosyl chloride and heterogeneous KOH in dioxane not only coronands from crown-4 to crown-8 can be obtained but also larger homologues.A systematic investigation has shown that: i) crown-9 and crown-10 can be formed from nona- and deca-ethylene glycol, respectively, and isolated in pure form; ii) the whole series of polyethylene glycols from tri- to deca-ethylene glycol yields not only the corresponding crown ethers but also higher cyclooligomers that can be analyzed up to about crown-20 by glc: in particular crown-12 and crown-16 were obtained from tetraethylene glycol and purified by column chromatography on cellulose; iii) the reaction, as applied to commercial mixtures of polyethylene glycols (from PEG 200 to PEG 1000), gives fairly high yields of crown ethers also in the region of large ring sizes.The contribution of the template effect of K(+) ion and the cyclooligomerization reactions for the various ring sizes are discussed.

The Ionic Hydrogen Bond. 2. Multiple NH+...O and CH?+...O Bonds. Complexes of Ammonium Ions with Polyethers and Crown Ethers

Complexes of ammonium ions RNH3+ (R = CH3, c-C6H11), (CH3)3NH+, and pyridineH+ with polyethers and crown ethers are observed in the gas phase in the abscence of the solvent effects.The dissociation energies, ΔH0D, of the RNH3+ polyether complexes range from 29.4 kcal mol-1 (for RNH3+*CH3OCH2CH2OCH3) to 46 kcal mol-1 (RNH3+*18-crown-6).The large ΔH0D values for complexes of polydentate ligands indicate multiple -NH+...O-hydrogen bonding.Such mutiple bonding can contribute up to 18 kcal mol-1 to the bonding in RNH3+*CH3(OCH2CH2)3OCH3 and 21 kcal mol-1 in RNH3+*18-crown-6.Multiple interactions are also evident in the (CH3)3NH+*polyether complexes where -CH?+...O-hydrogen bonding seems to occur; and consecutive -CH?+...O-bonds contribute approximately 6, 4, and 2 kcal/mol-1 respectively for up to three such bonds.Total ΔH0D values in the (CH3)3NH+*polyether complexes thus range from 26.7 kcal mol-1 in (CH3)3NH+*CH3O(CH2)2OCH3 to 41 kcal mol-1 in (CH3)3NH+*18-crown-6.Multiple interaction effects, possibly including van der Waals dispersion forces, are observed also in pyridineH+*polyether complexes.Large negative entropies in RNH3+*acyclic polyether complexes vs.RNH3+*cyclic crown ethers make the acyclic polyethers less efficient ligands.