2554-06-5

Basic information

• Product Name: 2,4,6,8-Tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane
• Synonyms: s-tetramethyltetravinylcyclotetrasiloxane;Tetravinyltetramethylcyclotetrasiloxane;tetravinyl-tetramethylcyclo-tetrasiloxane;2,4,6,8-TETRAMETHYL-2,4,6,8-TETRAVINYLCYCLOTETRASILOXANE;2,4,6,8-TETRAMETHYLTETRAVINYLCYCLOTETRASILOXANE;1,3,5,7-TETRAVINYLTETRAMETHYLCYCLOTETRASILOXANE;METHYLVINYLCYCLOSILOXANE;2,4,6,8-TETRAMETHYL2,4,6,8-TETRAVINYLCYCLO-TETRASILOXANE 99%
• CAS NO: 2554-06-5
• Molecular Formula: C₁₂H₂₄O₄Si₄
• Molecular Weight: 344.66
• EINECS: 219-863-1
• Product Categories: Si (Classes of Silicon Compounds);Siloxanes;Si-O Compounds;POSS IntermediatesPolymer Science;Silicone MonomersOrganometallic Reagents;Monomers;Organosilicon;POSS? Precursors and Intermediates;Silsesquioxanes: POSS? Nanohybrids
• Mol File: 2554-06-5.mol
• Article Data: 5

Chemical Properties

• Melting Point: −44 °C (dec.)(lit.)
• Boiling Point: 111-112 °C10 mm Hg(lit.)
• Flash Point: 210 °F
• Appearance: /liquid
• Density: 0.997 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.04mmHg at 25°C
• Refractive Index: n20/D 1.435
• Storage Temp.: 2-8°C
• Solubility: Miscible with most organic solvents.
• Water Solubility: 7μg/L at 23℃
• BRN: 1807272
• CAS DataBase Reference: 2,4,6,8-Tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane(CAS DataBase Reference)
• NIST Chemistry Reference: 2,4,6,8-Tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane(2554-06-5)
• EPA Substance Registry System: 2,4,6,8-Tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane(2554-06-5)

Safety Data

• Hazard Codes: Xi
• Statements: 36
• Safety Statements: 26-36
• WGK Germany: 1
• RTECS: GZ4550000
• F: 10
• TSCA: Yes
• Hazardous Substances Data: 2554-06-5(Hazardous Substances Data)

Usage

Chemical Properties

Colorless transparent liquid

Physical properties

bp 224–224.5 °C.

Uses

Different sources of media describe the Uses of 2554-06-5 differently. You can refer to the following data:
1. 2,4,6,8-Tetraethenyl-2,4,6,8-tetramethylcyclotetrasiloxane (1) (D4V) and the trimer, 2,4,6-triethenyl-2,4,6- trimethylcyclotrisiloxane (2) (D3V) are the two commercially available cyclic polyvinylmethylsiloxanes. D4 V is used as a vinyl donor in the palladium-catalyzed vinylation of aryl halides and as a building block in polymer chemistry and dendrimer synthesis. The palladium-catalyzed vinylation of substituted aryl halides using D4 V is a general and mild method for the preparation of a variety of substituted styrenes or dienes.It is widely used as reagent for the vinylation of aryl halides and building block for carbosilane dendrimers.
2. 2,4,6,8-Tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane is used as an intermediate in organic synthesis. It is used in the preparation of 4-vinyl-benzoic acid ethyl ester. Further, it is used to prepare styrene derivatives by cross-coupling with aryl bromide in the presence of palladium catalyst.

General Description

In the presence of a Pd catalyst, this reagent cross-couples with aryl bromides to give styrene derivatives.

Hazard

Low toxicity by ingestion and inhalation.

Flammability and Explosibility

Nonflammable

Purification Methods

A 7mL sample can be distilled in a small Vigreux column (p 11) at atmospheric pressure without polymerisation or decomposition. It is soluble in cyclohexane. [Kantor et al. J Am Chem Soc 77 1685 1955, Beilstein 4 IV 4184.]

InChI:InChI=1/C12H24O4Si4/c1-9-19(10-2)14-17(5,6)13-18(7,8)15-20(11-3,12-4)16-19/h9-12H,1-4H2,5-8H3

Synthetic route

chloro-trimethyl-silane (75-77-4) + Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7) + 1,1,1,3,5,7,7,7-octamethyl-3,5-divinyltetrasiloxane (16522-66-0) + 1,1,1,3,5,7,9,9,9-nonamethyl-3,5,7-trivinylpentasiloxane (16545-47-4)

Conditions	Yield
With water In toluene at 20℃; for 27h; Further byproducts given;	A n/a B n/a C 26% D 10 % Chromat.
With water In toluene at 20℃; for 27h; Further byproducts given;	A n/a B n/a C 26 % Chromat. D 10%

chloro-trimethyl-silane (75-77-4) + Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7) + 1,1,1,3,5,7,7,7-octamethyl-3,5-divinyltetrasiloxane (16522-66-0) + C18H42O5Si6 (34372-23-1)

Conditions	Yield
With water In toluene at 20℃; for 27h; Further byproducts given;	A n/a B n/a C 26% D 6 % Chromat.

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7)

Conditions	Yield
With water In toluene at 20℃; for 27h;	A 24% B 19 % Chromat.
With water In toluene at 20℃; for 27h;	A 26 % Chromat. B 12%

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5)

Conditions	Yield
With ethanol

chloro-trimethyl-silane (75-77-4) + Dichloromethylvinylsilane (124-70-9) → methylbis(trimethylsilyloxy)vinylsilane (5356-85-4) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7) + 1,1,1,3,5,7,7,7-octamethyl-3,5-divinyltetrasiloxane (16522-66-0)

Conditions	Yield
With water In toluene at 20℃; for 27h; Further byproducts given. Yields of byproduct given;	A 31 % Chromat. B n/a C n/a D n/a

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane (17704-22-2) + 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexavinyl-cyclohexasiloxane (18304-82-0) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7)

Conditions	Yield
With hydrogenchloride In toluene at 20℃; for 4h; Yield given. Further byproducts given. Yields of byproduct given;
With hydrogenchloride In toluene at 20℃; for 4h; Yield given. Yields of byproduct given;

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane (17704-22-2) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7)

Conditions	Yield
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;

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexavinyl-cyclohexasiloxane (18304-82-0) + 1,3,5-trimethyl-1,3,5-trivinyl-cyclotrisiloxane (3901-77-7) + 2,4,6,8,10,12,14-Heptamethyl-2,4,6,8,10,12,14-heptavinyl-1,3,5,7,9,11,13-heptaoxa-2,4,6,8,10,12,14-heptasila-cyclotetradecane (17704-23-3)

Conditions	Yield
With hydrogenchloride In toluene at 20℃; for 4h; Yield given. Further byproducts given. Yields of byproduct given;

methylvinyldiethoxysilane (5507-44-8) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexavinyl-cyclohexasiloxane

Conditions	Yield
With hydrogenchloride

Dichloromethylvinylsilane (124-70-9) + Octamethyltrisiloxane (107-51-7) → Hexamethyldisiloxane (107-46-0) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,1,1,3,5,7,9,9,9-nonamethyl-3,5,7-trivinylpentasiloxane (16545-47-4) + 1,1,1,3,5,5,7,7,9,9,9-undecamethyl-3-vinylpentasiloxane

Conditions	Yield
With dimethyl sulfoxide Heating; Further byproducts given. Title compound not separated from byproducts;

Dichloromethylvinylsilane (124-70-9) + Octamethyltrisiloxane (107-51-7) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane (17704-22-2) + 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexavinyl-cyclohexasiloxane (18304-82-0) + 1,1,1,3,5,7,7,9,9,9-decamethyl-3,5-divinylpentasiloxane

Conditions	Yield
With dimethyl sulfoxide at 20℃; Further byproducts given. Title compound not separated from byproducts;

Dichloromethylvinylsilane (124-70-9) → 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinylcyclopentasiloxane (17704-22-2)

Conditions	Yield
With 18-crown-6 ether; water at 20℃; for 0.5h; Overall yield = 90.1 %;

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 2,4,6,8-Tetramethyl-2,4,6,8-tetrakis-(2-trichlorosilanyl-ethyl)-[1,3,5,7,2,4,6,8]tetroxatetrasilocane (188593-65-9)

Conditions	Yield
With trichlorosilane; platinum on activated charcoal In tetrahydrofuran for 48h;	100%
With trichlorosilane; platinum on activated charcoal Addition;
With H3SiCl3; platinum on activated charcoal In tetrahydrofuran
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane; platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex In diethyl ether; xylene at -78℃; Stage #2: With trichlorosilane In diethyl ether; xylene at -78 - 20℃; for 20h;

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2-bromobenzoic acid ethyl ester (6091-64-1) → 2-ethenylbenzoic acid ethyl ester (32082-32-9)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran for 0.166667h; Hiyama Amino-Acrylate Synthesis; Inert atmosphere; Stage #2: 2-bromobenzoic acid ethyl ester In tetrahydrofuran at 50℃; for 8h; Inert atmosphere;	99%
With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 50℃; for 5h;	86%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2,6-diethyl-4,4-difluoro-1,3,5,7-tetramethyl-8-(4-iodophenyl)-4-bora-3a,4a-diaza-s-indacene → 2,6-diethyl-4,4-difluoro-8-(4-(methacryloyloxy)phenyl)-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene

Conditions	Yield
With tetrabutyl ammonium fluoride; bis(dibenzylideneacetone)-palladium(0); johnphos In tetrahydrofuran at 80℃; for 3h; Hiyama Coupling;	99%

Dichloromethylsilane (75-54-7) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 2,4,6,8-Tetrakis-[2-(dichloro-methyl-silanyl)-ethyl]-2,4,6,8-tetramethyl-[1,3,5,7,2,4,6,8]tetroxatetrasilocane (41454-29-9)

Conditions	Yield
platinum on activated charcoal for 12h; Ambient temperature;	97%
platinum on activated charcoal at 20℃; for 20h; Addition;	97%
10 % platinum-active carbon In tetrahydrofuran for 12h; Ambient temperature;	93%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2-bromoanthracene-9,10-dione (572-83-8) → 2-vinylanthracene-9,10-dione (13388-33-5)

Conditions	Yield
With tetrabutyl ammonium fluoride; bis(dibenzylideneacetone)-palladium(0); johnphos In tetrahydrofuran at 80℃; for 8h; Hiyama Coupling;	96%
With tetrabutyl ammonium fluoride; bis(dibenzylideneacetone)-palladium(0); johnphos In tetrahydrofuran at 80℃; for 8h; Inert atmosphere;	96%

2,2,4,6,8-pentamethylcyclotetrasiloxane (18163-78-5) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,1-dimethyl-3,3,3-triphenyl-3,3-1-vinyldisiloxane (1361991-02-7) → C28H44O5Si6

Conditions	Yield
Stage #1: 2,2,4,6,8-pentamethylcyclotetrasiloxane; 1,1-dimethyl-3,3,3-triphenyl-3,3-1-vinyldisiloxane In toluene at 60℃; for 0.166667h; Stage #2: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane In toluene at 80℃; for 1h;	95%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2-chloronaphthalene (91-58-7) → 2-Vinylnaphthalene (827-54-3)

Conditions	Yield
With XPhos; tetrabutyl ammonium fluoride; palladium diacetate In tetrahydrofuran at 67℃; for 24h; Reagent/catalyst; Hiyama Coupling; Schlenk technique; Inert atmosphere;	93%

dimethylmonochlorosilane (1066-35-9) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + acetic anhydride (108-24-7) → C28H64O12Si8

Conditions	Yield
Stage #1: dimethylmonochlorosilane; 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With dihydrogen hexachloroplatinate In isopropyl alcohol for 0.833333h; Inert atmosphere; Stage #2: acetic anhydride at 100℃; for 12h; Inert atmosphere;	93%

3-bromoquinoline (5332-24-1) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 3-ethenylquinoline (67752-31-2)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 20℃; for 0.25h; Inert atmosphere; Stage #2: 3-bromoquinoline In tetrahydrofuran at 50 - 62℃; for 2.83333h; Inert atmosphere;	91%
With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 50℃; for 3h;	89%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2-nitrophenyl bromide (577-19-5) → 2-nitrostyrene (579-71-5)

Conditions	Yield
With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 50℃; for 2h;	91%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + para-bromoacetophenone (99-90-1) → 1-(4-vinylphenyl)ethanone (10537-63-0)

Conditions	Yield
With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 50℃; for 4h;	91%
With sodium hydroxide; 4-hydroxyacetophenone oxime-derived palladacycle In water at 120℃; for 0.166667h; microwave irradiation;	21 % Spectr.

4-Cyanochlorobenzene (623-03-0) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 2-cyano-6-vinylnaphthalene (259199-33-2)

Conditions	Yield
With XPhos; tetrabutyl ammonium fluoride; palladium diacetate In tetrahydrofuran at 67℃; for 24h; Inert atmosphere; Schlenk technique;	91%

dimethylmonochlorosilane (1066-35-9) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + allylmagnesium bromide (2622-05-1) → C32H72O4Si8

Conditions	Yield
Stage #1: dimethylmonochlorosilane; 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex In toluene at 60℃; Inert atmosphere; Stage #2: allylmagnesium bromide In tetrahydrofuran at 60℃; for 1.16667h; Inert atmosphere; Cooling with ice;	91%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + Diphenylphosphine oxide (4559-70-0) → [(1,3,5,7-tetramethylcyclotetrasiloxane-1,3,5,7-tetrayl)tetra-2,1-ethanediyl]tetrakis[diphenylphosphine oxide] (369615-80-5)

Conditions	Yield
With tributyl borane In tetrahydrofuran; acetone at 0℃; for 14h; Solvent; Temperature; Reagent/catalyst; Inert atmosphere;	90%
With triethyl borane In tetrahydrofuran; hexane for 6h; Inert atmosphere;	89%

rac-3-sulfanylpropane-1,2-diol (96-27-5) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → C24H56O12S4Si4

Conditions	Yield
With 2,2-dimethoxy-2-phenylacetophenone In tetrahydrofuran at 20℃; for 2h; UV-irradiation;	90%
With 2,2'-azobis(isobutyronitrile) In acetonitrile at 70℃; for 18h;	85%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 4-Iodoacetophenone (13329-40-3) → 1-(4-vinylphenyl)ethanone (10537-63-0)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With tetrabutyl ammonium fluoride In tetrahydrofuran at 20℃; for 0.166667h; Stage #2: 4-Iodoacetophenone; bis(dibenzylideneacetone)-palladium(0) In tetrahydrofuran at 20℃; for 0.166667h;	88%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + methyl 6-chloro-2-naphtoate (5042-96-6) → methyl 6-vinyl-2-naphthoate (856011-08-0)

Conditions	Yield
With XPhos; tetrabutyl ammonium fluoride; palladium diacetate In tetrahydrofuran at 67℃; for 24h; Inert atmosphere; Schlenk technique;	88%

m-iodonitrobenzene (645-00-1) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 1-nitro-3-vinyl-benzene (586-39-0)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With tetrabutyl ammonium fluoride In tetrahydrofuran at 20℃; for 0.166667h; Stage #2: m-iodonitrobenzene; bis(dibenzylideneacetone)-palladium(0) In tetrahydrofuran at 20℃; for 0.166667h;	87%

bis(1,5-cyclooctadiene)nickel (0) (1295-35-8) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + triphenylphosphine (603-35-0) → [(Ni(PPh3))2(μ-(η-CH2CH(Me)Si(μ-O))4)] (306770-73-0)

Conditions	Yield
In diethyl ether byproducts: 1,5-C8H12; siloxane was added to Et2O soln. of equimolar amt. of Ni-complex and phosphine at ambient temp., mixt. was stirred overnight; volatiles were removed in vac., residue was taken up in pentane, mixt. was filtered through Celite, soln. was cooled to -30 °C, recrystd. from benzene at ambient temp., elem. anal.;	86%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + para-chloroacetophenone (99-91-2) → 1-(4-vinylphenyl)ethanone (10537-63-0)

Conditions	Yield
With XPhos; tetrabutyl ammonium fluoride; palladium diacetate In tetrahydrofuran at 67℃; for 24h; Inert atmosphere; Schlenk technique;	86%

1-iodoheptadecafluorooctane (507-63-1) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → C44H24F68I4O4Si4

Conditions	Yield
With sodium hydrogencarbonate; sodium dithionite In water; acetonitrile for 2h; under sonification;	85%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 4-iodobenzoic acid ethyl ester (51934-41-9) → ethyl 4-vinylbenzoate (2715-43-7)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With tetrabutyl ammonium fluoride In tetrahydrofuran at 20℃; for 0.166667h; Stage #2: 4-iodobenzoic acid ethyl ester; bis(dibenzylideneacetone)-palladium(0) In tetrahydrofuran at 20℃; for 0.166667h;	85%

bis(1,5-cyclooctadiene)nickel (0) (1295-35-8) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + Tri(p-tolyl)phosphine (1038-95-5) → [(Ni(PC6H4CH3-4))2(μ-(η-CH2CH(Me)Si(μ-O))4)] (306770-74-1)

Conditions	Yield
In diethyl ether byproducts: 1,5-C8H12; siloxane was added to Et2O soln. of equimolar amt. of Ni-complex and phosphine at ambient temp., mixt. was stirred overnight; volatiles were removed in vac., residue was taken up in pentane, mixt. was filtered through Celite, soln. was cooled to -30 °C, elem. anal.;	85%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 4-chlorobenzonitrile (100-00-5) → 4-nitrostyrene (100-13-0)

Conditions	Yield
With XPhos; tetrabutyl ammonium fluoride; palladium diacetate In tetrahydrofuran at 67℃; for 24h; Inert atmosphere; Schlenk technique;	85%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 2-hydroxyethanethiol (60-24-2) → C20H48O8S4Si4

Conditions	Yield
With 2,2'-azobis(isobutyronitrile) In acetonitrile at 70℃; for 18h;	85%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + 1,1-di-tert-butyl-2,3-dimethylsilirane → 2,4,6,8-tetrakis(1,1-di-tert-butylsiliran-2-yl)-2,4,6,8-tetramethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane

Conditions	Yield
With silver trifluoromethanesulfonate In toluene at 60℃; for 16h; Inert atmosphere; Schlenk technique;	85%

octamethylcyclotetrasiloxane (556-67-2) + 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) → 2-vinyl-2,4,4,6,6-pentamethylcyclotrisiloxane (18395-32-9)

Conditions	Yield
With triphenylphosphine; potassium hydroxide at 95 - 145℃; for 2h; Temperature; Concentration; Reagent/catalyst; Autoclave;	83.4%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + o-iodo-methyl-benzoic acid (610-97-9) → methyl o-vinylbenzoate (27326-44-9)

Conditions	Yield
Stage #1: 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane With triphenyl-arsane; tetrabutyl ammonium fluoride In tetrahydrofuran at 20℃; for 0.166667h; Stage #2: o-iodo-methyl-benzoic acid; bis(dibenzylideneacetone)-palladium(0) In tetrahydrofuran at 20℃; for 8h;	83%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + Ethyl 4-bromobenzoate (5798-75-4) → ethyl 4-vinylbenzoate (2715-43-7)

Conditions	Yield
With tetrabutyl ammonium fluoride; palladium(II) bromide; johnphos In tetrahydrofuran at 50℃; for 5h;	83%

2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (2554-06-5) + di(p-tolyl)phosphine oxide (2409-61-2) → C68H84O8P4Si4

Conditions	Yield
With triethyl borane In tetrahydrofuran; toluene at 25℃; for 12h; Inert atmosphere;	83%

Upstream product

• 124-70-9 Dichloromethylvinylsilane 
• 107-51-7 octamethyltrisiloxabe 
• 5507-44-8 methylvinyldiethoxysilane 
• 75-77-4 chloro-trimethyl-silane 

Downstream Products

• 10537-63-0 1-(4-vinylphenyl)ethanone 
• 1383474-28-9 ethyl 6-vinylpicolinate 
• 97410-25-8 1-(methylsulfonyl)-4-vinyl-benzene 
• 125889-39-6 5-vinyl-2-nitropyridine 
• 53498-47-8 N-(4-vinyl-phenyl)-acetamide 
• 100-13-0 4-nitrostyrene 
• 827-54-3 2-naphthylethylene 
• 13388-33-5 2-vinylanthracene-9,10-dione 
• 30765-95-8 N-p-toluenesulfonyl-2-vinylaniline 
• 28272-96-0 2-vinylbenzaldehyde 
• 23194-93-6 (Z)-5,6-dihydrodibenzo[b,f]azocine 
• 369615-80-5 [(1,3,5,7-tetramethylcyclotetrasiloxane-1,3,5,7-tetrayl)tetra-2,1-ethanediyl]tetrakis[diphenylphosphine oxide] 
• 306770-73-0 [(Ni(PPh3))2(μ-(η-CH2CH(Me)Si(μ-O))4)] 
• 306770-74-1 [(Ni(PC6H4CH3-4))2(μ-(η-CH2CH(Me)Si(μ-O))4)] 

Relevant articles and documents

Hydrocarbyl the cyclosiloxane preparation method (by machine translation)

The invention discloses a preparation method of alkyl cyclosiloxane. The preparation method is characterized by comprising the following steps: taking alkyl halogenosilane as a raw material, taking crown ether as a solvent and dropping the alkyl halogenosilane in a mixed solution formed by water and the crown ether while continuously stirring the alkyl halogenosilane; carrying out hydrolysis at a certain temperature to carry out condensation polymerization; standing after the reaction to carry out layering; and directly carrying out decompressed rectification on the obtained hydrolyzed oil to separate trialkylcyclotrisiloxane, tetraalkylcyclotetrasiloxane, pentaalkylcyclopentasiloxane and hexaalkylcyclohexasiloxane. The preparation method has the advantages that alcohols and low-boiling point hydrocarbons are not used as solvents, the crown ether is used as solvent and direct rectification is carried out on the prepared hydrolyzed oil to obtain the alkyl cyclosiloxane, so that the processes of washing, neutralization, drying and filtering are saved; and the solvent which undergoes standing and layering after the hydrolysis can be reused or can be cooled to a certain temperature to separate out the crown ether for recovery, so that the production cost is saved.

FEATURES OF INFLUENCE OF HCl ON HYDROLYTIC COPOLYCONDENSATION OF BIFUNCTIONAL ORGANOCHLOROSILANES WITH TRIMETHYLCHLOROSILANE

The hydrogen chloride that is formed in the hydrolytic copolycondensation of R'RSiCl2 with Me3SiCl affects the composition of the reaction products only at cocentrations above 30-35percent, where it is responsible for splitting out the terminal trimethylsiloxy group.The stability of the terminal groups increases with increasing size of the substituents on the silicon atom in the R'RSiCl2.The total yield of Me3SiO(R'RSiO)mSiMe3 with m = 1-4 also increases with increasing size of the substituents on the silicon atom in the R'RSiCl2.The total yield of p with p = 3-5 increases with decreasing tendency of the R'RSiCl2 to form rings by hydrolytic polycondensation, and with increasing sensitivity of the terminal trimethylsiloxy group in the cocondensation products to the action of HCl and its activity with respect to the siloxane bond.

REACTION OF ORGANOCHLOROSILANES WITH OXYGEN HETEROCYCLES AND LITHIUM

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