131832-48-9

Upstream product

• 131685-53-5 (S)-4-benzyl-3-propionyl-2-oxazolidinone 
• 78-84-2 isobutyraldehyde 
• 159734-07-3 C₂₁H₃₂BNO₃ 
• 590-86-3 isovaleraldehyde 

Downstream Products

• 380497-83-6 (5R,6R,7R)-5-Hydroxy-7-(4-methoxy-benzyloxy)-2,2,6,8-tetramethyl-nonan-3-one 
• 380497-85-8 (5S,6R,7R)-5-Hydroxy-7-(4-methoxy-benzyloxy)-2,2,6,8-tetramethyl-nonan-3-one 
• 162255-39-2 (4S,5R,6R)-4-Hydroxy-6-(4-methoxy-benzyloxy)-5,7-dimethyl-octan-2-one 
• 162303-39-1 (4R,5R,6R)-4-Hydroxy-6-(4-methoxy-benzyloxy)-5,7-dimethyl-octan-2-one 
• 176536-42-8 (2S,3R)-2,4-dimethyl-3-(p-methoxybenzyloxy)-pentan-1-ol 
• 162255-37-0 (2S,3R)-2,4-dimethyl-3-<(4-methoxybenzyl)oxy>pentanal 

Relevant academic research and scientific papers

α- and β-Lipomycin: Total syntheses by sequential stille couplings and assignment of the absolute configuration of all stereogenic centers

40 years ago spectroscopy, derivatization, and degradation revealed the structures of α-lipomycin and its aglycon β-lipomycin except for the configurations of their side-chain stereocenters. We synthesized all relevant β-lipomycin candidates: the (12R,13S

Lithium Amino Alkoxide-Evans Enolate Mixed Aggregates: Aldol Addition with Matched and Mismatched Stereocontrol

Building on structural and mechanistic studies of lithiated enolates derived from acylated oxazolidinones (Evans enolates) and chiral lithiated amino alkoxides, we found that amino alkoxides amplify the enantioselectivity of aldol additions. The pairing of enantiomeric series affords matched and mismatched stereoselectivities. The structures of mixed tetramers showing 2:2 and 3:1 (alkoxide-rich) stoichiometries are determined spectroscopically. Rate and computational studies provide a viable mechanistic and stereochemical model based on the direct reaction of the 3:1 mixed tetramers, but they raise unanswered questions for the 2:2 mixed aggregates.

Addition of kinetic boron enolates generated from β-alkoxy methyl ketones to aldehydes. Density functional theory calculations on the transition structures

Herein we report that good to excellent levels of 1,5-anti stereoinduction are obtained in boron enolate aldol reactions of 1,2-syn β-alkoxy methyl ketones with achiral aldehydes, when the β-alkoxy protecting group is part of a benzylidene acetal. We have

Stereoselective rearrangement of β-hydroxy-N-acyloxazolidin-2-ones to afford N-2-hydroxyethyl-1,3-oxazinane-2,4-diones

Zinc alkoxides of syn- or anti-β-hydroxy-N-acyloxazolidin-2-ones undergo stereoselective rearrangement to afford their corresponding syn- or anti-N-2-hydroxyethyl-1,3-oxazinane-2,4-diones in good yield.

Asymmetric aldol additions: Use of titanium tetrachloride and (-)-sparteine for the soft enolization of N-acyl oxazolidinones, oxazolidinethiones, and thiazolidinethiones

Asymmetric aldol additions using chlorotitanium enolates of N-acyloxazolidinone, oxazolidinethione, and thiazolidinethione propionates proceed with high diastereoselectivity for the Evans or non-Evans syn product depending on the nature and amount of the base used. With 1 equiv of titanium tetrachloride and 2 equiv of (-)-sparteine as the base or 1 equiv of (-)-sparteine and 1 equiv of N-methyl-2-pyrrolidinone, selectivities of 97:3 to >99:1 were obtained for the Evans syn aldol products using N-propionyl oxazolidinones, oxazolidinethiones, and thiazolidinethiones. The non-Evans syn aldol adducts are available with the oxazolidinethione and thiazolidinethiones by altering the Lewis acid/amine base ratios. The change in facial selectivity in the aldol additions is proposed to be a result of switching of mechanistic pathways between chelated and nonchelated transition states. The auxiliaries can be reductively removed or cleaved by nucleophilic acyl substitution. Iterative aldol sequences with high diastereoselectivity can also be accomplished.

A stereochemical model for merged 1,2- and 1,3-asymmetric induction in diastereoselective Mukaiyama aldol addition reactions and related processes

A systematic investigation of the direction and degree of stereoselectivity in aldol addition reactions is presented involving achiral unsubstituted metal enolate and enolsilane nucleophiles and chiral aldehydes. The BF3·OEt2 mediate