77-63-4

Basic information

• Product Name: 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane
• Synonyms: 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane;Cyclotetrasiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetraphenyl-;2,4,6,8-Tetramethyl-2,4,6,8-tetraphenyl-1,3,5,7-tetraoxa-2,4,6,8-tetrasilacyclooctane;2,4,6,8-Tetramethyl-2,4,6,8-tetraphenylcyclooctanetetrasiloxane;2,4,6,8-Tetraphenyl-2,4,6,8-tetramethylcyclooctanetetrasiloxane;Tetrtaphenyltetramethylcyclotetrasiloxane;1,3,5,7-Tetramethyltetraphenylcyclotetrasiloxane;2,4,6,8-Tetramethyl-2,4,6,8-tetraphenyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane
• CAS NO: 77-63-4
• Molecular Formula: C₂₈H₃₂O₄Si₄
• Molecular Weight: 544.9
• EINECS: 201-045-0
• Product Categories: Catalysis and Inorganic Chemistry;Chemical Synthesis
• Mol File: 77-63-4.mol
• Article Data: 6

Chemical Properties

• Melting Point: 99°C
• Boiling Point: 493.2°C at 760 mmHg
• Flash Point: 211.7°C
• Appearance: /solid
• Density: 1.13
• Vapor Pressure: 2.17E-09mmHg at 25°C
• Refractive Index: 1.5461
• BRN: 2957579
• CAS DataBase Reference: 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane(CAS DataBase Reference)
• NIST Chemistry Reference: 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane(77-63-4)
• EPA Substance Registry System: 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane(77-63-4)

Safety Data

• WGK Germany: 3
• RTECS: NI6755100
• Hazardous Substances Data: 77-63-4(Hazardous Substances Data)

Usage

Uses

Reactant for synthesis of ethylhydrosilicone fluids

InChI:InChI=1/C28H32O4Si4/c1-33(25-17-9-5-10-18-25)29-34(2,26-19-11-6-12-20-26)31-36(4,28-23-15-8-16-24-28)32-35(3,30-33)27-21-13-7-14-22-27/h5-24H,1-4H3

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%

diethoxy-methyl-phenyl-silane (775-56-4) → 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4)

Conditions	Yield
With sodium hydroxide

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.);

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;;

carbon dioxide (124-38-9) + methylphenylsilane (766-08-5) → 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4)

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

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;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + chromium(0) hexacarbonyl (199620-14-9, 13007-92-6) → (CH3Si(C6H5)O)4(Cr(CO)3)4 (98719-24-5, 98719-23-4, 98679-13-1, 98719-25-6)

Conditions	Yield
In tetrahydrofuran; dibutyl ether cyclotetrasiloxane and Cr(CO)6 were dissolved in Bu2O-THF under N2, soln. was heated under reflux for 122 h; soln. was cooled, passed through a short column of Florisil/Celite, volatiles were removed under vac., residue recrystd. from benzene;	79%

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + 1,3-bis-(2,4-dichloro-benzoyloxymethyl)-1,1,3,3-tetramethyl-disiloxane (18666-42-7) → 1,11-bis-(2,4-dichloro-benzoyloxymethyl)-1,1,3,5,7,9,11,11-octamethyl-3,5,7,9-tetraphenyl-hexasiloxane (119722-21-3)

Conditions	Yield
With sulfuric acid

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) → 2-hydrido-2,4,6-trimethyl-4,6-diphenylcyclotrisiloxane (60472-60-8)

Conditions	Yield
at 465 - 480℃;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) → 1-hydro-1,3,5,7-tetramethyl-3,5,7-triphenylcyclotetrasiloxane (61469-87-2)

Conditions	Yield
at 465 - 480℃;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + butan-1-ol (71-36-3) → tributoxy-methyl-silane (5581-68-0)

Conditions	Yield
(i) (heating), (ii) /BRN= 969148/, aq. LiOH; Multistep reaction;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + butan-1-ol (71-36-3) → Biphenyldibutoxymethylsilan (61469-88-3)

Conditions	Yield
(i) (heating), (ii) /BRN= 969148/, aq. LiOH; Multistep reaction;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + butan-1-ol (71-36-3) → 1,3-Bis-(dibutoxy-methyl-silanyl)-benzene (61469-89-4)

Conditions	Yield
(i) (heating), (ii) /BRN= 969148/, aq. LiOH; Multistep reaction;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + butan-1-ol (71-36-3) → 1,4-Bis-(dibutoxy-methyl-silanyl)-benzene (61469-90-7)

Conditions	Yield
(i) (heating), (ii) /BRN= 969148/, aq. LiOH; Multistep reaction;

2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) + butan-1-ol (71-36-3) → di(butoxy)(methyl)(phenyl)silane (15576-83-7)

Conditions	Yield
(i) (heating), (ii) /BRN= 969148/, aq. LiOH; Multistep reaction;

methanedisulfonic acid (503-40-2) + 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane (77-63-4) → 3-Methyl-3-phenyl-2,4-dioxa-1,5-dithia-1,1,5,5-tetraoxid-3-silacyclohexane

Conditions	Yield
Stage #1: methanedisulfonic acid at 100℃; for 2h; Inert atmosphere; Stage #2: 2,4,6,8-tetraphenyl-2,4,6,8-tetramethylcyclotetrasiloxane With 1,3-dimethyl-2-imidazolidinone at 190 - 200℃; for 9.5h; Inert atmosphere;	46 g

Upstream product

• 775-56-4 diethoxy-methyl-phenyl-silane 
• 149-74-6 dichloromethylphenylsilane 
• 124-38-9 carbon dioxide 
• 766-08-5 methylphenylsilane 

Downstream Products

• 119722-21-3 1,11-bis-(2,4-dichloro-benzoyloxymethyl)-1,1,3,5,7,9,11,11-octamethyl-3,5,7,9-tetraphenyl-hexasiloxane 
• 60472-60-8 2-hydrido-2,4,6-trimethyl-4,6-diphenylcyclotrisiloxane 
• 61469-87-2 1-hydro-1,3,5,7-tetramethyl-3,5,7-triphenylcyclotetrasiloxane 
• 5581-68-0 tributoxy-methyl-silane 
• 61469-89-4 1,3-Bis-(dibutoxy-methyl-silanyl)-benzene 
• 61469-90-7 1,4-Bis-(dibutoxy-methyl-silanyl)-benzene 
• 15576-83-7 di(butoxy)(methyl)(phenyl)silane 

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