17881-63-9

Upstream product

• 75-78-5 dimethylsilicon dichloride 
• 4294-57-9 para-methylphenylmagnesium bromide 
• 4342-61-4 1,2-dichlorotetramethylsilane 
• 874-60-2 4-methyl-benzoyl chloride 
• 106-43-4 para-chlorotoluene 
• 106-38-7 para-bromotoluene 
• 701-35-9 p-tolyltrichlorosilane 
• 75-24-1 trimethylaluminum 
• 18236-57-2 methyl-4-methylphenyl-dichlorosilane 
• 18055-70-4 1,3-bis(4′-tolyl)-1,1,3,3-tetramethyldisiloxane 

Downstream Products

• 17920-15-9 (4-methylphenyl)dimethylsilanol 
• 18055-70-4 1,3-bis(4′-tolyl)-1,1,3,3-tetramethyldisiloxane 
• 67347-08-4 N-(p-Tolylmethylsilyl)-acetamid 
• 19960-78-2 n-Butyl-dimethyl-p-tolylsilan 
• 68469-58-9 (4-Chloro-butyl)-dimethyl-p-tolyl-silane 
• 68469-59-0 (4-Bromo-butyl)-dimethyl-p-tolyl-silane 
• 66870-89-1 1,1,1-trimethyl-3,3-dimethyl-3-tolyldisiloxane 
• 64277-83-4 C₁₃H₂₁NO₂Si 
• 68469-65-8 dimethylpropyl(p-tolyl)silane 
• 68469-61-4 allyldimethyl(4-methylphenyl)silane 
• 36376-61-1 Dimethyl(4-methylphenyl)silylethyne 
• 17988-22-6 ethoxy(dimethyl)(p-tolyl)silane 
• 33664-05-0 (p-Methoxy-phenyl)-dimethyl-fluor-silan 
• 5971-96-0 1,1,2,2-tetramethyl-1,2-bis(4-tolyl)disilane 

Relevant academic research and scientific papers

Synthesis of octacarboxy spherosilicate

A feasible new preparation was reported for an octacarboxylphenyl functionalized spherosilicate, octakis[(pcarboxyphenyl) dimethylsilyl]silicate, which was a versatile monomer leading to other functional spherosilicate derivatives. The synthesis was start

Ru-Catalyzed Geminal Hydroboration of Silyl Alkynes via a New gem-Addition Mechanism

While 1,2-addition represents the most common mode of alkyne hydroboration, herein we describe a new 1,1-hydroboration mode. It is the first demonstration of gem-(H,B) addition to an alkyne triple bond. With the superior [CpRu(MeCN)3]PF6 catalyst, a range of silyl alkynes reacted efficiently with HBpin under mild conditions to form various synthetically useful silyl vinyl boronates with complete stereoselectivity and broad functional group compatibility. An extension to germanyl alkynes and the hydrosilylation of alkynyl boronates toward the same type of products were also achieved. Mechanistically, this process features a new pathway featuring gem-(H,B) addition to form the key α-boryl-α-silyl Ru-carbene intermediate followed by silyl migration. It is believed that the orbital interaction between boron and Cβ in the coplanar relationship between the boron atom and the ruthenacyclopropene ring preceding boron migration is responsible for the new reactivity. Control experiments and DFT (including molecular dynamics) calculations provided important insights into the mechanism, which excluded the involvement of a metal vinylidene intermediate. This study represents a new step forward not only for alkyne hydroboration but also for other geminal additions of alkynes.

METHOD FOR PRODUCING ARYLSILANE COMPOUND CONTAINING HALOSILANE COMPOUND AS RAW MATERIAL

PROBLEM TO BE SOLVED: To provide a method for producing an arylsilane compound with low production cost. SOLUTION: A method for producing an arylsilane compound includes a reaction step for the cross-coupling reaction of a halosilane compound represented by general formula (A-1), (A-2), or (A-3) and an arylboronic acid pinacol ester in the presence of a nickel catalyst, a Lewis acid catalyst, and an organic base (R independently represent an aromatic hydrocarbon group, a heteroaromatic ring group, or a C1-20 hydrocarbon group; X independently represent a halogeno group or a trifluoromethanesulfonyloxy group). SELECTED DRAWING: None COPYRIGHT: (C)2020,JPOandINPIT

Nickel-Catalyzed Selective Cross-Coupling of Chlorosilanes with Organoaluminum Reagents

Nickel-catalyzed cross-coupling reactions of chlorosilanes with organoaluminum reagents were developed. An electron-rich Ni(0)/PCy3 complex was found to be an effective catalyst for the desired transformation. The reaction of dichlorosilanes 1 proceeded to give the corresponding monosubstituted products 2. Trichlorosilanes 4 underwent selective double substitution to furnish the corresponding monochlorosilanes 2. Overall, the selective synthesis of a series of alkylmonochlorosilanes 2 from di- and trichlorosilanes was achieved using the present catalytic systems.

Enantioselective 1,2-Anionotropic Rearrangement of Acylsilane through a Bisguanidinium Silicate Ion Pair

Highly enantioselective bisguanidinium-catalyzed tandem rearrangements of acylsilanes are reported. The acylsilanes were activated via an addition of fluoride on the silicon to form a penta-coordinate anionic silicate intermediate. The silicate then underwent alkyl or aryl group migration from the silicon atom to the neighboring carbonyl carbon atom (1,2-anionotropic rearrangement), followed by [1,2]-Brook rearrangement to provide the secondary alcohols in high yields with excellent enantioselectivities (up to 95% ee). The isolation of an α-silylcarbinol intermediate as well as DFT calculations revealed that the 1,2-anionotropic rearrangement occurred via a bisguanidinium silicate ion pair, which is the stereodetermining step. The chiral center formed is then retained without inversion through the subsequent [1,2]-Brook rearrangement. Crotyl acylsilanes were smoothly transformed into homoallylic linear crotyl alcohols with retention of E/Z geometry, and no branched alcohols were detected. This clearly suggested that the 1,2-anionotropic rearrangement occurred through a three-membered instead of a five-membered transition state.

Unbridged 1- and 2-substituted bis(silylindenyl) zirconium(IV) and hafnium(IV) dichloride complexes as catalyst precursors for ethylene polymerization

Twelve unbridged metallocene dichloride complexes of the types [1-(4-XC6H4SiMe2)-η5-Ind]2MCl2 and [2-(4-XC6H4SiMe2)-η5-Ind]2MCl2 (X = Me, MeO, F; M = Zr, Hf) with differently 1- and 2-substituted indenyl ligands have been synthesized, characterized and applied for catalytic ethylene polymerization. After activation with methylaluminoxane (MAO), all complexes are catalysts for ethylene polymerization. However, in nearly all cases, the species with the silyl substituent in the 1-position show much higher activities than those with the same substituent in 2-position of the indenyl moiety. For instance, the MAO activated complex bis(η5-1-(dimethyl-4-tolylsilyl)idenyl) zirconium(IV) dichloride (3), displayed an almost five times higher activity (3980 kg PE/mol cat.h) than the isomeric bis(η5-2-(dimethyl-4-tolylsilyl)indenyl) zirconium(IV) dichloride (19)/MAO catalyst (870 kg PE/mol cat.h). The same trend was observed for the para-fluorophenyl silyl indenyl complexes 23 and 17. This behavior may be explained in a way that the same silyl substituent in position 2 can exert more steric hindrance around the metal center compared to the 1-substituted analogues. The GPC characterization of the produced polyethylenes showed that some of the resins have a bimodal molecular weight distribution indicating at least two different active sites that are involved in the polymerization process.

Synthesis and helix-sense-selective polymerization of a novel phenylacetylene having a trisiloxanyl group and two hydroxyl groups and enantioselective permeability of the resulting chiral polymeric membrane: Effect of the trisiloxanyl group on the polymerization and enantioselective permeability

To develop a new phenylacetylene monomer suitable for helix-sense-selective polymerization (HSSP) we reported previously and to improve the efficiency of the HSSP and membrane performance of the resulting polymer, a novel phenylacetylene having a trisiloxanyl group (S3BDHPA) was synthesized and polymerized by using a chiral catalytic system and enantioselectivity in permeation of its membrane was examined. S3BDHPA was suitable for the HSSP and the CD absorption of poly(S3BDHPA) was stronger and more stable than that of the corresponding polymer having no siloxanyl groups. In addition, enantioselectivity in permeation of poly(S3BDHPA) was much higher than that of a polymer membrane having no siloxanyl groups. They are thought to be caused by the flexibility and hydrophobicity of the trisiloxane groups.

New achiral phenylacetylene monomers having an oligosiloxanyl group most suitable for helix-sense-selective polymerization and for obtaining good optical resolution membrane materials

To develop new phenylacetylene monomers more suitable for helix-sense-selective polymerization (HSSP) we reported previously and to improve the efficiency of the HSSP and membrane performance of the resulting polymers, novel phenylacetylenes having a flexible oligosiloxanyl group (SnBDHPA)together with the other related three series of monomers were synthesized and polymerized by using a chiral catalytic system and enantioselectivity in permeation of the membranes from the resulting chiral polymers were examined. SnBDHPA was the most suitable for the HSSP and the CD absorptions (G values) of poly- (SnBDHPA) were stronger and more stable than those of the corresponding polymers having rigid alkyl groups. The polymers could be fabricated to flexible self-supporting membranes by using solvent-casting method. In addition, enantioselectivity in permeation of one of poly(SnBDHPA) membranes was much higher than that of a poly(phenylacetylene) membrane having alkyl groups. This was because the polymers having oligosiloxane groups had high regularity of structures, i.e., chemical structures of the macromolecules such as one handedness and high order structures such as columnar contents in the membranes, and the membranes were flexible and had almost no defects. These good properties as optical resolution membrane materials were caused by flexibility, hydrophobicity, and bulkiness of the oligosiloxane chains. S3BDHPA having a trisiloxanyl group was found to be the best monomer for the HSSP and for obtaining good optical resolution membrane materials.

Silver-catalyzed transmetalation between chlorosilanes and aryl and alkenyl Grignard reagents for the synthesis of tetraorganosilanes

(Chemical Equation Presented) The silver savior: Nucleophilic substitution reactions of chlorosilanes with aryl Grignard reagents have been developed which take place under silver catalysis to afford tetraorganosilanes (see scheme). This transformation is likely to be promoted by diarylargentate reagents that are generated in situ.

Stereocontrol in organic synthesis using silicon-containing compounds. Syntheses of (±)-2-deoxyribonolactone and (±)-arabonolactone

Samarium iodide reacts with methyl (Z)-3-dimethyl(4-methylphenyl)silylprop-2-enoate 5b to give dimethyl (3RS,4SR)-3,4-bis[dimethyl(4-methylphenyl)silyl]hexane-1,6-dioate 8b with high stereoselectivity. This meso diester can be converted into (3RS,4SR)-3,4-bis[dimethyl(4-methylphenyl)silyl]pentan-5-olide 16 by Dieckmann cyclisation, demethoxycarbonylation and Baeyer-Villiger reaction. Silyl-to-hydroxy conversion and relactonisation gave (±)-deoxyribonolactone, and anti-selective enolate hydroxylation followed by silyl-to-hydroxy conversion gave (±)-arabonolactone. An attempt to synthesise sugars with the relative configuration (3RS,4RS) was thwarted by an unprecedented retention of configuration at the migration origin in the cationic rearrangement of (3RS,4SR)-3,4-bis[dimethyl(4-methylphenyl)silyl]-5-hydroxypentanoic acid 28 to (3RS,4SR)-3,5-bis[dimethyl(4-methylphenyl)silyl]pentan-1,4-olide 30.