18412-74-3

Upstream product

• 994-30-9 triethylsilyl chloride 
• 1589-82-8 phenylmagnesium bromide 
• 60-29-7 diethyl ether 
• 1112-48-7 triethyl-bromo-silane 
• 6921-34-2 benzylmagnesium chloride 
• 617-86-7 triethylsilane 
• 108-88-3 toluene 
• 100-44-7 benzyl chloride 
• 770-10-5 benzyltrichlorosilane 
• 2386-64-3 ethylmagnesium chloride 
• 1666-17-7 benzaldehyde p-toluenesulfonylhydrazone 
• 97025-65-5 N'-benzylidene-2-nitrobenzenesulfonohydrazide 
• 100-52-7 benzaldehyde 

Downstream Products

• 37628-30-1 (α-Brombenzyl)triethylsilan 
• 648428-83-5 (α,α-dibromobenzyl)triethylsilane 
• 63935-93-3 benzoyltriethylsilane 
• 86392-93-0 (+/-)-(α-hydroxybenzyl)triethylsilane 
• 648428-52-8 (Triethylsilanyl-trimethylsilanyloxy-methyl)-benzene 
• 37628-28-7 (Phenyl-triethylsilanyl-methyl)-phosphonic acid diethyl ester 

Relevant academic research and scientific papers

Synthesis of Optically Pure Arylsilylcarbinols and Their Use as Chiral Auxiliaries in Oxacarbenium Ion Reactions

A family of arylsilylcarbinols was synthesized and investigated as chiral auxiliaries for oxacarbenium ion reactions. The optically pure arylsilylcarbinols were prepared using Noyori's transfer hydrogenation catalyst 11. The transfer hydrogenation shows very good enantioselectivities and turnover efficiency for the aryl silyl ketones and is the method of choice for preparing these optically pure alcohols. The diastereoselective addition of allyltrimethylsilane to an in situ generated oxacarbenium ion was explored using Marko's conditions. The selectivity for a representative aliphatic aldehyde was very good, but the selectivity was significantly reduced with unsaturated and aromatic aldehydes. The range of selectivities with different auxiliaries was narrow, and the most practical auxiliary is the phenylsilylcarbinol 2.

Development of Novel Phosphino-Oxazoline Ligands and Their Application in Asymmetric Alkynlylation of Benzylic Halides

A new set of stereochemically diverse phosphino-oxazoline ligands derived from simple L-amino acids and 2-(diphenylphosphaneyl)benzoic acid were developed. Those mono anionic tridentated N,N,P-ligands promote the Cu-catalyzed enantioselective radical coupling of terminal alkynes with a broad range of benzylic halides including benzo-fused cyclic α-halides and α-silyl benzyl halides in high yield and excellent enantioselectivity under mild reaction conditions. With multi distinct sites for structural modification, a diverse pool of chiral N,N,P-ligands is readily accessed, allowing for rapid optimization of the ligand structure for a specific substrate. Notably, the enantioselective alkynlylation of benzylic halides bonds in benzo-cyclic molecules has also been realized for the first time.

Ruthenium-Catalyzed Brook Rearrangement Involved Domino Sequence Enabled by Acylsilane-Aldehyde Corporation

A ruthenium-catalyzed [1,2]-Brook rearrangement involved domino sequence is presented to prepare highly functionalized silyloxy indenes with atomic- and step-economy. This domino reaction is triggered by acylsilane-directed C-H activation, and the aldehyde controlled the subsequent enol cyclization/Brook Rearrangement other than β-H elimination. The protocol tolerates a broad substitution pattern, and the further synthetic elaboration of silyloxy indenes allows access to a diverse range of interesting indene and indanone derivatives.

Tertiary α-Silyl Alcohols by Diastereoselective Coupling of 1,3-Dienes and Acylsilanes Initiated by Enantioselective Copper-Catalyzed Borylation

An efficient synthesis of functionalized tertiary α-silyl alcohols by an enantio- and diastereoselective copper-catalyzed three-component coupling of 1,3-dienes, bis(pinacolato)diboron, and acylsilanes is reported. The reaction proceeds well with different 1,3-dienes and a broad range of aryl- as well as alkenyl- but also alkyl-substituted acylsilanes. The target compounds are formed with high regio-, diastereo-, and enantioselectivity (up to 99 % ee and d.r. >20:1) and are highly versatile synthetic building blocks.

Palladium(0)-catalyzed C(sp3)-Si bond formation: Via formal carbene insertion into a Si-H bond

Pd(0)-Catalyzed formal carbene insertion into Si-H bonds has been achieved as an efficient method for C(sp3)-Si bond formation. The reaction, which uses readily available N-tosylhydrazones as the diazo precursors, is highly efficient and shows a wide substrate scope. Rh(ii) and Cu(i) salts, which are the widely used catalysts for carbene insertion reactions, have been proved to be ineffective for the current reaction. A Pd(ii) carbene migratory insertion/reductive elimination mechanism is proposed.

Iron Porphyrin Catalyzed Insertion Reaction of N-Tosylhydrazone-Derived Carbenes into X-H (X = Si, Sn, Ge) Bonds

An efficient Fe(TPP)Cl catalyzed insertion reaction of in situ generated benzylic carbenes from N-tosylhydrazones into X-H (X = Si, Sn, Ge) was developed. Silanes bearing tertiary, secondary, and primary (3°, 2°, and 1°) Si-H bonds all reacted well to afford insertion products in moderate to high yields (up to 97%), and the reaction time could be significantly shortened to 1 h under microwave irradiation. A programmable stepwise double insertion strategy was developed for the synthesis of unsymmetrical tetrasubstituted silanes.

Silver(i)-promoted insertion into X-H (X = Si, Sn, and Ge) bonds with N-nosylhydrazones

Silver(i)-promoted carbene insertion into X-H (X = Si, Sn, and Ge) bonds has been realized by using unstable diazo compounds, which are generated in situ from N-nosylhydrazones as carbene precursors. The reaction tolerates a wide range of functional groups and delivers a number of valuable silicon-containing compounds in very high yields (up to 96%). Moreover, organostannanes and organogermanes were as well effectively obtained in very good yields under optimal conditions.

Enantioselective Synthesis of Chiral 3-Substituted-3-silylpropionic Esters via Rhodium/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation

We have successfully developed the asymmetric hydrogenation of β-silyl-α,β-unsaturated esters to prepare chiral 3-substituted-3-silylpropionic ester products catalyzed by rhodium/bisphosphine-thiourea (ZhaoPhos) with excellent results (up to 97% yield, >99% ee, 1500 TON). Moreover, our hydrogenation products can be efficiently converted to other important organic molecules, such as chiral ethyl (R)-3-hydroxy-3-phenylpropanoate or (R)-3-[dimethyl(phenyl)silyl]-3-phenylpropanoic acid. (Figure presented.).

SILYLATION OF AROMATIC HETEROCYCLES BY EARTH ABUNDANT TRANSITION-METAL-FREE CATALYSTS

The present invention describes chemical systems and methods for silylating aromatic organic substrates, said system or method comprising or consisting essentially of a mixture of (a) at least one organosilane and (b) at least one strong base, the definition of strong base now also including hydroxide, especially KOH, said system being preferably, but not necessarily substantially free of a transition-metal compound, and said methods comprising contacting a quantity of the organic substrate with a mixture of (a) at least one organosilane and (b) at least one strong base, under conditions sufficient to silylate the aromatic substrate; wherein said system is substantially free of a transition-metal compound.

Silylation of C-H bonds in aromatic heterocycles by an Earth-abundant metal catalyst

Heteroaromatic compounds containing carbon-silicon (C-Si) bonds are of great interest in the fields of organic electronics and photonics, drug discovery, nuclear medicine and complex molecule synthesis, because these compounds have very useful physicochemical properties. Many of the methods now used to construct heteroaromatic C-Si bonds involve stoichiometric reactions between heteroaryl organometallic species and silicon electrophiles or direct, transition-metal-catalysed intermolecular carbon-hydrogen (C-H) silylation using rhodium or iridium complexes in the presence of excess hydrogen acceptors. Both approaches are useful, but their limitations include functional group incompatibility, narrow scope of application, high cost and low availability of the catalysts, and unproven scalability. For this reason, a new and general catalytic approach to heteroaromatic C-Si bond construction that avoids such limitations is highly desirable. Here we report an example of cross-dehydrogenative heteroaromatic C-H functionalization catalysed by an Earth-abundant alkali metal species. We found that readily available and inexpensive potassium tert-butoxide catalyses the direct silylation of aromatic heterocycles with hydrosilanes, furnishing heteroarylsilanes in a single step. The silylation proceeds under mild conditions, in the absence of hydrogen acceptors, ligands or additives, and is scalable to greater than 100 grams under optionally solvent-free conditions. Substrate classes that are difficult to activate with precious metal catalysts are silylated in good yield and with excellent regioselectivity. The derived heteroarylsilane products readily engage in versatile transformations enabling new synthetic strategies for heteroaromatic elaboration, and are useful in their own right in pharmaceutical and materials science applications.