22661-04-7

Upstream product

• 53172-83-1 2-methyl-3-phenyl-1-butene 
• 93-55-0 1-phenyl-propan-1-one 
• 37471-46-8 1-phenyl-1-trimethylsiloxypropene 
• 76886-35-6 3-(benzyloxy)-2-methyl-1-phenylpropan-1-one 
• 28557-00-8 phenylzinc chloride 
• 100-58-3 phenylmagnesium bromide 
• 54541-41-2 methyl 2-methyl-3-phenylbutanoate 
• 61211-96-9 1-chloro-1,1-diphenyl-2,2,2-trimethyldisilane 
• 219547-24-7 [(3-iodo-2-methylbutan-1-oxy)diphenylsilyl]trimethylsilane 
• 216592-89-1 3-iodo-2-methylbutyl benzenesulfonate 
• 14367-28-3 methyl (2E)-2-methyl-3-phenylbut-2-enoate 
• 75-24-1 trimethylaluminum 
• 53432-99-8 trans-3-methyl-2-phenyloxetane 

Relevant academic research and scientific papers

Stereoselective radical aryl migrations from sulfur to carbon

Stereoselective radical 1,5 aryl migrations from sulfur (in arenesulfonates) to carbon with diastereoselectivities of up to 14:1 are presented.

Alkyl Ethers as Traceless Hydride Donors in Br?nsted Acid Catalyzed Intramolecular Hydrogen Atom Transfer

A new protocol for the deoxygenation of alcohols and the hydrogenation of alkenes under Br?nsted acid catalysis has been developed. The method is based on the use of either a benzyl or isopropyl ether as a traceless hydrogen-atom donor, and involves an intramolecular hydride transfer as a key step, which is achieved in a regio- and stereoselective manner.

Divergent Synthetic Access to E- and Z-Stereodefined All-Carbon-Substituted Olefin Scaffolds: Application to Parallel Synthesis of (E)- and (Z)-Tamoxifens

A highly substrate-general synthesis of all-carbon-substituted E- and Z-stereodefined olefins is performed. The method comprises two sets of parallel and stereocomplementary preparations of (E)- and (Z)-α,β-unsaturated esters involving two robust and distinctive reactions: 1) stereocomplementary enol tosylations using readily available TsCl/diamine/(LiCl) base reagents, and 2) stereoretentive Negishi cross-coupling using the catalysts [Pd(dppe)Cl2] (for E) and [Pd(dppb)Cl2] (for Z). The present parallel approach is categorized as both type I (convergent approach: 16 examples, 56–87 % yield) and type II (divergent approach: 18 examples, 70–95 % yield). The obtained (E)- and (Z)-α,β-unsaturated ester scaffolds are successfully transformed into various E- and Z-stereodefined known and novel olefins (8×2 derivatization arrays). As a demonstration, application to the parallel synthesis of both (E)- and (Z)-tamoxifens, a representative motif of all-carbon-substituted olefins, is accomplished in a total of eight steps with an overall yield of 58 % (average 93 %) and 57 % (average 93 %), respectively.

Stereoselective phenyl migration from silicon to carbon

In the present letter, the first stereoselective radical 1,5 phenyl transfer from silicon to carbon is reported. Diphenyl(trimethylsilyl)silyl ethers, the corresponding germylated and stannylated derivatives, and also some silyl ethers derived from commercially available silicon protecting groups were tested in this ipso substitution reaction. Diastereoselectivities of up to 11:1 were obtained.

Highly diastereoselective acetal cleavages using novel reagents prepared from organoaluminum and pentafluorophenol

Chiral acetals derived from aldehydes and (-)-(2R,4R)-2,4-pentanediol are cleaved selectively by organoaluminum reagents. The reaction proceeds via the retentive-alkylation process with >95% selectivities in most cases. Trialkylaluminum reagent is utilized for higher alkyl transfers, but for smaller alkyl transfers, a new reagent system, combining trialkylaluminum and the halophenols such as pentafluorophenol and 2,4,6-trichlorophenol, is employed. Chiral acetals derived from aldehydes and 1,3-butanediol are cleaved selectively by trialkylaluminum, even for smaller alkyl transfers. Oxetane is also exposed to these aluminum reagents, and the retentive-alkylation products are obtained stereoselectively. The reaction of acetals derived from (-)-(2R,4R)-2,4-pentanediol and ketones in the presence of a catalytic amount of aluminum pentafluorophenoxide produces reductively cleaved products with high diastereoselectivity. The reaction is a new means of diastereoselective cleavage of acetals: an intramolecular Meerwein-Ponndorf-Verley reductive and Oppenauer oxidative reaction on an acetal template.