124306-44-1

Upstream product

• 16837-43-7 2-benzoylpropanal 
• 925-90-6 ethylmagnesium bromide 
• 79314-55-9 3-hydroxy-2-methyl-1-phenylpentan-1-one 
• 627-21-4 2-Pentyne 
• 100-52-7 benzaldehyde 
• 17180-49-3 2-methyl-1-phenylpent-4-en-1-one 
• 58625-96-0 ethyl 2-methyl-2-pentenoate 
• 93-55-0 1-phenyl-propan-1-one 
• 37471-46-8 1-phenyl-1-trimethylsiloxypropene 
• 71268-59-2 (E)-1-phenyl-1-(trimethylsiloxy)propene 

Downstream Products

• 857973-57-0 2-methyl-1,3-diphenyl-pentan-1-one 
• 87514-18-9 Trimethyl-((1Z,3E)-2-methyl-1-phenyl-penta-1,3-dienyloxy)-silane 
• 90013-12-0 (R)-2-methyl-1-phenyl-1-pentanone 
• 872884-41-8 (S)-(+)-2-methyl-1-phenylpentan-1-one 
• 1312031-65-4 C₂₀H₂₁ClO₂S 

Relevant academic research and scientific papers

Borane-Catalyzed Direct Asymmetric Vinylogous Mannich Reactions of Acyclic α,β-Unsaturated Ketones

Herein, we report that, by using chiral bicyclic bisborane catalysts, we have achieved the first highly regio-, diastereo-, and enantioselective direct asymmetric vinylogous Mannich reactions of acyclic α,β-unsaturated ketones. The strong Lewis acidity and steric bulk of the bisborane catalysts were essential for the observed high yields and selectivities.

Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones

Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir-N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated yields. Challenging dialkyl substituted substrates, which are difficult to hydrogenate with satisfactory chiral induction, were hydrogenated in a highly enantioselective fashion.

Pd-Boron-Catalyzed One Carbon Isomerization of Olefins: Water Assisted Process at Room Temperature

A palladium-boronate/borane-system -catalyzed isomerization of olefins has been uncovered. An efficient catalytic combination of [Pd(OAc)2]3-boronate-PCy3-enabled olefin isomerization at 80 °C has been investigated. Addition of water to the reaction showed a remarkable improvement and the isomerization occurred at ambient temperature. These catalytic systems function efficiently for the isomerization of functionalized as well as unfunctionalized olefins. The catalytic conditions demonstrate the involvement of both nonhydride and metal-hydride medium and can be switchable with water as an additive.

Alkyne hydroacylation: Switching regioselectivity by tandem ruthenium catalysis

By using tandem Ru-catalysis, internal alkynes can be coupled with aldehydes for the synthesis of β,γ-unsaturated ketones. The catalyst promotes alkyne transformations with high regioselectivity, with examples that include the differentiation of a methyl vs ethyl substituent on the alkyne. Mechanistic studies suggest that the regioselectivity results from a selective allene formation that is governed by allylic strain.

Highly enantioselective synthesis of optically active ketones by iridium-catalyzed asymmetric hydrogenation

(Chemical Equation Presented) Close to perfect enantioselectivity (up to 99% ee, see scheme) is found for the formation of α-substituted ketones by the asymmetric hydrogenation of enones with an iridium-phosphinooxazoline catalyst. In an operationally simple process, both linear and cyclic substrates react well and afford the desired products in high yields. A wide variety of substituents are tolerated, thus making the method synthetically appealing.

Diastereomer-differentiating photochemistry of β-arylbutyrophenones: Yang cyclization versus type II elimination

The diastereomers of ketones 2 and 3 are shown to exhibit distinct photochemical reactivities due to conformational preferences; while the anti isomers of 2 and 3 undergo efficient Yang cyclization in 75-90% yields with a remarkable diastereoselectivity (> 90%), the syn isomers predominantly undergo Norrish Type II elimination. The differences in the product profiles of the diastereomers are consistent with a mechanistic picture involving the formation of precursor diastereomeric triplet 1,4-biradicals in which the substituents at α and β-positions stabilize the cisoid (cyclization) or transoid (elimination) geometry. The fact that such a diastereomeric relationship does indeed ensue at the triplet-excited-state itself is demonstrated via the nanosecond laser-flash photolysis of model ketones 1. The diastereomeric discrimination in the product profiles observed for ketones 2 and 3 as well as in the triplet lifetimes observed for ketones 1 can both be mechanistically traced back to different conformational preferences of the ground-state diastereomeric ketones and the intermediary 1,4-biradicals. Additionally, it emerges from the present study that the syn and anti diastereomers of ketones 2 and 3 represent two extremes of a broad range of widely examined butyrophenones, which lead to varying degrees of Yang photocyclization depending on the alkyl substitution pattern.

α:γ RATIOS IN PHENYLTHIOMETHYLATION OF SILYL DIENOL ETHERS

We report α:γ ratios for the electrophilic attack of phenylthiomethyl chloride on all the possible 2- and 4-methylated 1-phenyl-1-trimethylsilyloxybutadienes (7a-7e); the methyl groups appear to reduce the proportion of attack taking place at the carbon atom carrying the methyl groups.