546-45-2

Basic information

• Product Name: 1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE
• Synonyms: 2,4,6-Trimethyl-2,4,6-triphenyl-1,3,5,2,4,6-trioxatrisilinane;2,4,6-trimethyl-2,4,6-triphenyl-cyclotrisiloxan;Cyclotrisiloxane, 2,4,6-trimethyl-2,4,6-triphenyl-;PHENYLMETHYLCYCLOSILOXANES;TRIPHENYLTRIMETHYLCYCLOTRISILOXANE;2,4,6-TRIMETHYL-2,4,6-TRIPHENYLCYCLOTRISILOXANE;1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE;1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE, MIXED CIS,TRANS ISOMERS
• CAS NO: 546-45-2
• Molecular Formula: C₂₁H₂₄O₃Si₃
• Molecular Weight: 408.67
• EINECS: 208-900-7
• Product Categories: Chemical Synthesis;Organometallic Reagents;Organosilicon;Siloxanes
• Mol File: 546-45-2.mol
• Article Data: 8

Chemical Properties

• Melting Point: 100°C
• Boiling Point: 160-90°C 5mm
• Flash Point: >200°C
• Appearance: /solid
• Density: 1.102 g/mL at 20 °C(lit.)
• Vapor Pressure: 2.58E-06mmHg at 25°C
• Refractive Index: 1.545
• Storage Temp.: Sealed in dry,Room Temperature
• BRN: 2954104
• CAS DataBase Reference: 1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE(546-45-2)
• EPA Substance Registry System: 1,3,5-TRIMETHYL-1,3,5-TRIPHENYLCYCLOTRISILOXANE(546-45-2)

Safety Data

• Statements: 20/21/22
• Safety Statements: 24/25-36/37/39
• WGK Germany: 3
• TSCA: Yes
• Hazardous Substances Data: 546-45-2(Hazardous Substances Data)

Usage

Chemical Properties

Colorless to white solid

InChI:InChI=1/C21H24O3Si3/c1-25(19-13-7-4-8-14-19)22-26(2,20-15-9-5-10-16-20)24-27(3,23-25)21-17-11-6-12-18-21/h4-18H,1-3H3

Synthetic route

dichloromethylphenylsilane (149-74-6) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4)

Conditions	Yield
With pyridine; sodium hydrogencarbonate In acetone at 20℃; for 3h;	A 33% B 65.5%
With tetrahydrofuran; lithium at 35 - 45℃; Product distribution; Mechanism;
With tetrahydrofuran; lithium at 35 - 45℃; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

dichloromethylphenylsilane (149-74-6) → 2.4.6.8.10-Pentamethyl-2.4.6.8.10-pentaphenyl-cyclopentasiloxan (34239-75-3) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + cis-trans-cis-2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (15331-54-1)

Conditions	Yield
With water In tetrahydrofuran for 10h; Heating;	A n/a B n/a C n/a D 11%

dichloromethylphenylsilane (149-74-6) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2)

Conditions	Yield
(i) (hydrolysis), (ii) H2SO4, toluene; Multistep reaction;

methylphenylsilane (766-08-5) → bis(phenyl methyl hydrido)disiloxane (6689-22-1) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + methylphenylsiloxane (7110-06-7, 147377-21-7, 147377-32-0) + C14H18O2Si2 (142684-18-2)

Conditions	Yield
With water for 2h; Ambient temperature; Further byproducts given;	A 19 % Chromat. B 32 % Chromat. C 2.3 % Chromat. D 17 % Chromat.

C11H18O2Si → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + tert-butyl alcohol (75-65-0)

Conditions	Yield
In nonane at 160℃; Rate constant; Kinetics; Thermodynamic data; ΔE(excit.);

(2-phenylpropan-2-ylperoxy)methyl(phenyl)silane (70996-44-0) → 1-methyl-1-phenylethyl alcohol (617-94-7) + bis(phenyl methyl hydrido)disiloxane (6689-22-1) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + poly(methylphenylsiloxane) (4543-12-8)

Conditions	Yield
In nonane at 160℃; Rate constant; Kinetics; Thermodynamic data; ΔE(excit.);

dichloromethylphenylsilane (149-74-6) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + cis-1,3,5-trimethyl-1,3,5-triphenylcyclorisiloxane (3424-57-5) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4)

Conditions	Yield
With H2O In diethyl ether; water addn. of H2O to a soln. of (CH3)(C6H5)SiCl2 in ether;;

dichloromethylphenylsilane (149-74-6) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + cis-1,3,5-trimethyl-1,3,5-triphenylcyclorisiloxane (3424-57-5)

Conditions	Yield
With H2O In water pouring (CH3)(C6H5)SiCl2 into icewater under vigorous stirring;; distn. at 2 torr; recrystn. from alc.;;

d7-N,N-dimethylformamide (4472-41-7) + methylphenylsilane (766-08-5) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + trimethylamine-d7 (150730-19-1)

Conditions	Yield
With Pt(0) nanoparticles immobilized on a monolithic polymeric support at 20℃; Catalytic behavior;

methylphenylsilane (766-08-5) + 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane (25015-63-8) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + C13H21BO3Si

Conditions	Yield
With basolite C300; water In acetonitrile at 70℃; for 7h; Inert atmosphere;

methylphenylsilane (766-08-5) → 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4)

Conditions	Yield
With water; 2,3-Dihydro-1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene In acetonitrile at 20℃; for 0.1h; Time; Temperature; Solvent; Schlenk technique; Glovebox;

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4300, Mw/Mn=2.69; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	91%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4800, Mw/Mn=2.10; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	90%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4200, Mw/Mn=2.01; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	88%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4300, Mw/Mn=2.17; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	85%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4300, Mw/Mn=1.89; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	82%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4200, Mw/Mn=1.66; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	80%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4000, Mw/Mn=1.62; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	80%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4200, Mw/Mn=1.67; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	79%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4200, Mw/Mn=1.93; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	77%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4100, Mw/Mn=1.65; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	75%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4100, Mw/Mn=1.70; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	74%

chloro-trimethyl-silane (75-77-4) + 2,4,6-trimethylcyclotrisiloxane (13269-39-1) + Hexamethylcyclotrisiloxane (541-05-9) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → polymer, Mn=4000, Mw/Mn=1.50; monomers: hexamethylcyclotrisiloxane; trimethyltriphenylcyclosiloxane; trimethylcyclotrisiloxane

Conditions	Yield
Stage #1: 2,4,6-trimethylcyclotrisiloxane; Hexamethylcyclotrisiloxane; 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane With n-butyllithium In tetrahydrofuran; hexane at 70℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane	73%

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + chromium(0) hexacarbonyl (199620-14-9, 13007-92-6) → (CH3Si(C6H5)O)3(Cr(CO)3)3 (98719-22-3, 98679-12-0)

Conditions	Yield
In tetrahydrofuran; dibutyl ether cyclotrisiloxane and Cr(CO)6 were dissolved in Bu2O-THF under N2, soln.was heated under reflux for 68 h; soln. was cooled, passed through a short column of Florisil/Celite, volatiles were removed under vac., residue recrystd. from benzene;	68%

4-Iodoacetophenone (13329-40-3) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → biphenyl-4-acetaldehyde (92-91-1)

Conditions	Yield
With silver(l) oxide; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran at 60℃;	55%

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → methyldifluorophenylsilane (328-57-4) + 1,3-difluoro-1,3-diphenyl-1,3-dimethyldisiloxane (26487-75-2) + C21H24F2O2Si3 (150885-59-9) + C21H25FO3Si3

Conditions	Yield
With sodium tetrafluoroantimonate(III) for 0.5h; Heating;	A 45% B n/a C n/a D n/a

para-iodoanisole (696-62-8) + 1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) → 4-methoxylbiphenyl (613-37-6)

Conditions	Yield
With silver(l) oxide; tetrakis(triphenylphosphine) palladium(0) In tetrahydrofuran at 60℃; for 120h;	39%

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + chromium(0) hexacarbonyl (199620-14-9, 13007-92-6) → (Si3O3(C6H5)3(CH3)3)Cr(CO)3 (116837-66-2, 116837-67-3, 116745-88-1) + (Si3O3(C6H5)3(CH3)3){Cr(CO)3}2 (116837-68-4, 116745-89-2)

Conditions	Yield
In n-heptane; diethylene glycol boiling mixt. of Cr(CO)6, excess ligand, diglyme and heptane for 5-6 h (Ar); Filtn., removal of solvent (vac.), chromy. on column with (silica gel, 10:1 petroleum ether-CH2Cl2), eluation of yellow zone (CH2Cl2), evapn. (vac.), sepn. of complexes by thin layer chromy. on silica gel in 2:1 C6H6/petroleum ether mixt.; elem. anal.;	A 32% B n/a

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + acetic anhydride (108-24-7) → di(acetoxy)methyl(phenyl)silane (17998-91-3)

Conditions	Yield
With iron(III) chloride

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + acetic anhydride (108-24-7) → 1.3-Dimethyl-1.3-diphenyl-disiloxan-1.3-diol-diacetat (18054-23-4)

Conditions	Yield
With iron(III) chloride

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + acetic anhydride (108-24-7) → 1.3.5-Trimethyl-1.3.5-triphenyl-trisiloxan-1.5-diol-diacetat (18763-06-9)

Conditions	Yield
With iron(III) chloride

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + dimethylsilicon dichloride (75-78-5) → 1.13-Dichlor-1.1.3.5.7.9.11.13-octamethyl-3.5.7.9.11.13-hexaphenyl-heptasiloxan (18828-67-6)

Conditions	Yield
at 250℃;

1,3,5-triphenyl-1,3,5-trimethylcyclotrisiloxane (546-45-2) + dimethylsilicon dichloride (75-78-5) → 1.7-Dichlor-1.1.3.5.7-pentamethyl-3.5.7-triphenyl-tetrasiloxan (18782-95-1)

Conditions	Yield
at 250℃;

Upstream product

• 149-74-6 dichloromethylphenylsilane 
• 766-08-5 methylphenylsilane 
• 70996-44-0 (2-phenylpropan-2-ylperoxy)methyl(phenyl)silane 
• 4472-41-7 d₇-N,N-dimethylformamide 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 

Downstream Products

• 17998-91-3 di(acetoxy)methyl(phenyl)silane 
• 18054-23-4 1.3-Dimethyl-1.3-diphenyl-disiloxan-1.3-diol-diacetat 
• 18763-06-9 1.3.5-Trimethyl-1.3.5-triphenyl-trisiloxan-1.5-diol-diacetat 
• 92-91-1 biphenyl-4-acetaldehyde 
• 613-37-6 4-methoxylbiphenyl 
• 116837-66-2 (Si₃O₃(C₆H₅)3(CH₃)3)Cr(CO)3 
• 116837-68-4 (Si₃O₃(C₆H₅)3(CH₃)3){Cr(CO)3}2 

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