2615-23-8

Upstream product

• 1825-69-0 dimethyl chloro ethoxy silane 
• 106-37-6 1.4-dibromobenzene 
• 78-62-6 diethoxy dimethylsilane 

Downstream Products

• 163086-42-8 1,4-Bis-(dimethyl-prop-1-ynyl-silanyl)-benzene 
• 1078-97-3 1,4-bis(dimethylchlorosilyl)benzene 
• 2754-32-7 1,4-bis(hydroxydimethylsilyl)benzene 
• 18784-67-3 p-Phenylen-bis-(1,1,3,3-tetramethyl-3-phenyl-disiloxan) 

Relevant academic research and scientific papers

Siloxa-bridged-cyclophanes featuring benzene, thiophene and pyridine units

Two octamethyldisiloxa-bridged [3.3]cyclophanes (1 and 2) and a dodecamethyltrissiloxa-bridged [3.3.3]-cage compound (3) were prepared by hydrolysis of the chlorosilyl monomers. This general route was also employed for the preparation of two octamethyldisiloxa-bridged [3.3]heterophanes featuring two thiophene (14) or pyridine (17) moities.

Efficient zirconocene-coupling of silicon-substituted diynes to polymers and macrocycles

The zirconocene-coupling of diynes with internal silicon substituents, MeC≡CMe2SiArSiMe2C≡CMe (1: Ar = 1,4-C6H4; 2: Ar = 1,3-C6H4; 3: Ar = 1,3-C6H4; 3: Ar = 4,4'-C6H4C6H4), generates regiospecific polymers containing zirconacyclopentadiene in the main chain (5-7). These organometallic polymers hydrolyze cleanly to butadienediyl polymers of the type [Me2SiArSiMe2CH = CMeCMe = CH](n) (11-13), and polymer 5 reacts with iodine to give the iodine-containing polymer [1,4-Me2SiC6H4SiMe2C(I)=CMeCMe=C(I)](n) (14). The organometallic polymers undergo facile and high-yield degradations to macrocycles under mild conditions (refluxing tetrahydrofuran solution). The size and shape of the resulting macrocycles depend upon the nature of the diyne spacer group. Thus, polymers 5 and 7 containing parallel diyne units convert to the trimeric macrocycles [Me2SiArSiMe2C4Me2ZrCp2]3 (15: Ar = 1,4-C6H4; 24: Ar = 4,4'- C6H4C6H4), while polymer 6 gives the dimeric macrocycle [1,3- Me2SiC6H4SiMe2C4Me2ZrCp2]2 (18). The dimeric macrocycle [Me2SiC6H4SiMe2C6H4SiMe2C4Me2ZrCp2]2 (20) was obtained directly from the zirconocene coupling of Me2Si[(1,4-C6H4)- SiMe2(C≡CMe)]2 (4) by heating the reaction mixture to reflux. In a similar manner, the diyne Me2Si(C≡CMe)2 was converted in high yield to the hexameric macrocycle [Me2SiC4Me2ZrCp2]6 (22). The macrocycles 15, [1,4-Me2SiC6H4SiMe2C4Me2H2]3 (16), and 18 were characterized by single-crystal X-ray crystallography. Molecules of 15 adopt a nearly planar C3 macrocyclic structure with a cavity described by an average transannular Si···Si distance of 13.2 A?, while the hydrolyzed macrocycle 16 has a chair conformation. This conformation change results from conversion of cis diene groups in the zirconacyclopendiene fragments to trans diene groups in 16. The high- yield formation of macrocycles apparently results from the reversible nature of the alkyne-coupling reaction, which allows for a low-energy pathway to the smallest macrocycle possessing minimal ring strain.

Process for producing aromatic-containing silicone compounds

An improved process for producing an aromatic containing silicon compound comprising reacting an aromatic organic compound of the formula RXa with a silicon compound of the formula Rb ' Si Z4-b in the presence of molar quantities of Mg and from 0.5 to up to 1 mole of a promoter which is preferably tetrahydrofuran per mole of the aromatic compound where R is preferably phenylene, X is chloro, a is 2, R' is preferably methyl, Z is alkoxy of 1 to 8 carbon atoms and b is equal to 2.