122948-53-2

Upstream product

• 66107-30-0 4-bromophenyl trifluoromethanesulfonate 
• 762-72-1 allyl-trimethyl-silane 
• 13170-43-9 (trimethylsilyl)methylmagnesium chloride 
• 99-90-1 para-bromoacetophenone 
• 122948-58-7 1-(4-bromophenyl)vinyl trifluoromethanesulfonate 
• 106-41-2 4-bromo-phenol 
• 619-42-1 4-methoxycarbonylphenyl bromide 
• 494205-61-7 2-(4-bromo-phenyl)-1,3-bis-trimethylsilanyl-propan-2-ol 
• 1822-00-0 trimethylsilylmethyllithium 

Downstream Products

• 494205-62-8 C₂₃H₃₄O₂Si₂ 
• 1234908-92-9 (1-bromo-4-(3-fluoroprop-1-en-2-yl))benzene 
• 445399-06-4 4-[4-({1-[(trimethylsilyl)methyl]ethenyl}phenyl)dimethylsilyl]benzaldehyde 
• 402718-38-1 di[4-(1-trimethylsilanylmethyl-vinyl)phenyl]dimethylsilane 

Relevant academic research and scientific papers

Enantioselective Synthesis of α-Allyl Amino Esters via Hydrogen-Bond-Donor Catalysis

We report a chiral-squaramide-catalyzed enantio- and diastereoselective synthesis of α-allyl amino esters. The optimized protocol provides access to N-carbamoyl-protected amino esters via nucleophilic allylation of readily accessible α-chloro glycinates. A variety of useful α-allyl amino esters were prepared, including crotylated products bearing vicinal stereocenters that are inaccessible through enolate alkylation, with high enantioselectivity (up to 97% ee) and diastereoselectivity (>10:1). The reactions display first-order kinetic dependence on both the α-chloro glycinate and the nucleophile, consistent with rate-limiting C-C bond formation. Computational analysis of the uncatalyzed reaction predicts an energetically inaccessible iminium intermediate, and a lower energy concerted SN2 mechanism.

Catalytic Geminal Difluorination of Styrenes for the Construction of Fluorine-rich Bioisosteres

A geminal difluorination of alkenes based on I(I)/I(III) catalysis is disclosed, which is compatible with a range of electronically and substitutionally diverse styrenes (27 examples, up to 89% yield). Employing inexpensive p-TolI as the organocatalyst, turnover is enabled by Selectfluor-mediated oxidation to generate the ArIF2 species in situ. Extension to include α-substituted styrenes bearing fluorine-containing groups is disclosed and provides an expansive platform for the generation of fluorine-rich architectures.

Silver-promoted cross-coupling of substituted allyl(trimethyl)silanes with aryl iodides by palladium catalysis

A ligand-free Pd-catalyzed cross-coupling of substituted allyl(trimethyl)silanes with aryl iodides enabled by silver salts was developed. This reaction delivered allylic arenes chemoselectively and regioselectively. The study suggested that the reaction might proceed through oxidative addition of ArI to Pd(0) followed by halide abstraction to give an electrophilic complex ArPdX, which further reacted with allyl(trimethyl)silanes via electrophilic addition/desilylation/reductive elimination to afford the allyl-aryl coupling products.

Syntheses of mono-, di-, and trifluorinated styrenic monomers

Concise syntheses of gram quantities of three fluorinated -methylstyrenic monomers suitable for polymerisation studies are disclosed, all based on the use of reasonably priced commercially available starting materials and reagents. Georg Thieme Verlag Stuttgart New York.

Asymmetric synthesis of chiral polymers by means of repetitive addition of allylsilane to aldehyde

Monomers having both allyltrimethylsilyl and formyl groups were prepared. Chiral (acyloxy)borane initiated the repetitive polyaddition of the monomers to give optically active polymers having main chain configurational chirality. Optical purity of the chiral polymer was evaluated by the analysis of the degradation product.

Asymmetric polymer synthesis by repetitive Sakurai-Hosomi allylation reaction of compounds possessing both formyl and allylsilane functions

Trialkylallylsilanes generally react with aldehydes in the presence of a Lewis acid to the corresponding homoallylic alcohols. Chiral Lewis acids promote the same reaction to yield the enantiomerically-enriched homoallylalcohols. We have prepared four compounds (7-10) that possess both formyl and allylsilane functions. Lewis acids initiated self-polyaddition reactions of these compounds by means of repetitive allylation. The use of chiral Lewis acids resulted in the formation of optically active polymers that possess exo-methylene and secondary OH functions in their main chain. The optical purity of these chiral polymers was estimated based on the results of model asymmetric reactions between benzaldehyde and β-substituted allylsilanes and by controlled degradation.

Asymmetric allylation polymerization of bis(allylsilane) and dialdehyde containing Si-phenyl linkage

Repetitive Sakurai-Hosomi allylation between dialdehyde and bis(allylsilane) yielded a polymer having stereogenic carbons in its main chain. In the presence of an enantiopure Lewis acid catalyst such as chiral (acyloxy)borane (CAB), the allylation polymerization proceeded in a stereoselective manner to give optically active polymers. We have prepared new monomers containing Si-phenyl linkages for the asymmetric allylation polymerization. After polymerization, the Si-phenyl linkages in the main chain could be cleaved easily to give the corresponding chiral homoallylic alcohol. The enantiomeric purity of the chiral polymer was then evaluated by chiral HPLC analysis of the alcohol obtained from the degradation.