114418-30-3

Upstream product

• 2747-38-8 methyltrichlorotitanium 
• 81445-44-5 (S)-2-(benzyloxy)propanal 
• 18006-13-8 methyltriisopropoxytitanium(IV) 
• 100-39-0 benzyl bromide 
• 195375-00-9 ethyl (3R,1'R,2'S)-3-(2'-hydroxy-1'-methylpropyloxy)-2,2-dimethyl-5-phenyl-4-pentynoate 
• 1029272-42-1 (2R,3S)-2,3-butanediol 
• 199122-75-3 (1S,4R,5R,6S)-5-[(R)-((1R,2S)-2-Benzyloxy-1-methyl-propoxy)-methoxy-methyl]-6-methyl-bicyclo[2.2.1]hept-2-ene 
• 54783-72-1 ethyl (S)-2-(benzyloxy)propionate 
• 113133-46-3 3-(phenylmethoxy)butan-2-one 
• 69087-52-1 (2S,3S)-4,5-dimethyl-2-phenyl-1,3-dioxolane 
• 114418-31-4 (2S,3S)-3-Benzyloxy-butan-2-ol 
• 100-52-7 benzaldehyde 
• 53346-05-7 2-(benzyloxy)propanal 
• 917-54-4 methyllithium 

Relevant academic research and scientific papers

First direct NMR spectroscopic observation of a Cram-chelate involving a chiral α-alkoxy aldehyde

The reaction of CH3TiCl3 with 2-benzyloxy propanal 10 at low temperatures in CD2Cl2 leads to the formation of two diastereomeric Cram-type chelates 13a/13b which can be observed directly by 13C-NMR spectroscopy. The octahedral chelates undergo C---C bond formation with first order kinetics, suggesting intramolecular 1,3 methyl transfer. Crossover experiments are unsuitable for definitive proof of intramolecularity due to ligand exchange reactions prior to Grignard-type addition.

Asymmetric Induction by a Nitrogen14N/15N Isotopomer in Conjunction with Asymmetric Autocatalysis

Chirality arising from isotope substitution, especially with atoms heavier than the hydrogen isotopes, is usually not considered a source of chirality in a chemical reaction. An N2,N2,N3,N3-tetramethyl-2,3-butan

Reductive cleavage of acetals and ketals with 9-borabicyclo[3.3.1]nonane

The reductive cleavage of benzaldehyde acetals and acetophenone ketals with the air-stable crystalline 9-borabicyclo[3.3.1]-nonane dimer provides monobenzylated ether derivatives of diols and 1,2-oxygen-transposed β-phenethyl alcohols, respectively. The boron moiety is effectively recovered through simple procedures which involve convenient air-stable reagents and boron byproducts. The process is particularly selective for 1,3-diols giving the more substituted monobenzyl ether derivatives exclusively. With acetophenone ketals both reduction and elimination occur, permitting 9-BBN-H to hydroborate the resulting styrene to produce 1,2-oxygen-transposed β-phenethyl alcohols cleanly. Potential applications of this new process were illustrated with the synthesis of the hallucinogen, mescaline, and the analgesic, ibufenac.

Diastereoselectivity in the reduction of α-oxy- and α-amino-substituted acyclic ketones by polymethylhydrosiloxane

Diastereoselectivity in the reduction of α-alkoxy-, α-acyloxy-, and α-alkylamino-substituted ketones with polymethylhydrosiloxane (PMHS) in the presence of fluoride ion catalysis was investigated. High syn-selectivity was observed in the reduction of α-alkoxy, α-acyloxy, and α-dialkylamino ketones. Reduction of α-monoalkylamino ketone proceeded in anti-selective manner with moderate selectivity. The observed selectivity is explained based on Felkin-Anh and Cram-chelate models.

Hydrogenation of α-Keto Ethers: Dynamic Kinetic Resolution with a Heterogeneous Modified Catalyst and a Heterogeneous Base

The first successful example of the asymmetric hydrogenation of substituted α-keto ethers with Cinchona-modified Pt/Al2O3 is reported. In the absence of an additional base, kinetic resolution of the racemic starting material was observed with high diastereoselectivity and ee's up to 98% at conversions of a strong reaction acceleration but racemic product. Immobilization of OH- on solid ion exchangers resulted in the desired dynamic kinetic resolution, and ee's of >80% were obtained at >95% conversion. These effects are rationalized on the basis of a simple kinetic and structural model.

Chiral oxazaborolidinone-mediated enantioselective ring-cleavage reaction of a mixture of diastereomeric 1,3-dioxolane acetals: Application to asymmetric desymmetrization of meso-1,2-diols

Ring-cleavage reaction of a mixture of diastereomeric dioxolane acetals syn- and anti-1b-e proceeds in an enantiodifferentiating manner in the presence of chiral Lewis acid 2. The reaction is utilized as a key step in asymmetric desymmetrization of meso-1,2-diols.

Asymmetric desymmetrization of saturated and unsaturated meso-1,2-diols

An asymmetric desymmetrization of saturated and unsaturated cyclic and acyclic meso-1,2-diols has been developed from the ene acetals, prepared from the norbornene carboxyaldehyde and meso-1,2-diols. The intramolecular haloetherification of the ene acetals as a key step afforded 8-membered acetals in a stereoselective manner just by the reaction of norbornene olefin even when the ene acetals from unsaturated meso-1,2-diols having olefins in the same molecule were used. Subsequent reductive elimination, followed by protecting the hydroxy group and transacetalization, gave optically active 1,2-diol derivatives and the starting ene acetals in good yields. (C) 2000 Elsevier Science Ltd.

Chelation-controlled reduction of α- and β-oxygenated ketones with lithium tri-n-butylborohydride

Lithium tri-n-butyl borohydride showed high selectivity in the reduction of α- and β-oxygenated ketones, giving a preponderance of the chelation controlled products.

Methylaluminum bis(4-substituted-2,6-di-tert-butylphenoxide) as an efficient nonchelating Lewis acid: Application to asymmetric Diels-Alder reaction and diastereoselective alkylation to alkoxy carbonyl substrates

The exceptionally bulky methylaluminum bis(4-substituted-2,6-di-tert-butylphenoxide) such as MAD or MABR can be successfully utilized as a highly efficient nonchelating Lewis acid for achieving high stereoselectivity in 1,n asymmetric induction in cyclic