191283-11-1

Upstream product

• 287978-11-4 4-acetyl-3-acetylamino-5-oxohexanoic acid 1,2-bis(2-methylphenyl)-2-hydroxyethyl ester 
• 172277-06-4 (4S,5S)-2-Bromomethyl-4,5-di-o-tolyl-[1,3]dioxolane 

Downstream Products

• 191283-14-4 3,4,4a,5,6,7-hexahydro-5,5-dimethyl-4'S,5'S-bis(2-methylphenyl)spiro[8H-2-benzopyran-3,2'-[1,3]-dioxolan]-8-one 
• 287978-07-8 4-acetylamino-3,4-dihydro-6-methyl-4'S,5'S-bis(2-methylphenyl)-5-(1-oxoethyl)spiro[2H-pyran-2,2'-[1,3]dioxolan] 
• 287978-11-4 4-acetyl-3-acetylamino-5-oxohexanoic acid 1,2-bis(2-methylphenyl)-2-hydroxyethyl ester 

Relevant academic research and scientific papers

Stereoselective routes to substituted β-amino carbonyl compounds via heterodiene [4π+2π] cycloadditions of auxiliary-based C2 symmetric ketene acetals

Heterodiene [4π+2π] cycloadditions of (S,S)-4,5-diaryl-2-methylene-1,3-dioxolanes 1 to a series of β-amido-α,β-unsaturated carbonyl compounds are diastereoselective (d.r.≥4:1). The products can be purified by trituration or crystallisation and hydrolysed with acid to generate the corresponding β-amido carbonyl compounds, the overall sequence effecting an auxiliary-based enantioselective conjugate addition of an acetate enolate, leading to β-aminoacid derivatives.

Stereoselective routes to substituted β-amino carbonyl compounds via heterodiene cycloadditions of an auxiliary-based C2-symmetric ketene acetal

Heterodiene cycloadditions of (S,S)-4,5-bis(o-tolyl)-2-methylene-1,3- dioxolane 1 with a series of substituted β-amido-α,β-unsaturated carbonyl compounds are diastereoselective (dr ≥ 4:1). The cycloadducts from N-(2-(1- oxoethyl)-3-oxobut-1-enyl)ethanamide 2a can be purified by crystallisation and hydrolysed with acid to generate the corresponding β-amidoacetic esters, the sequence providing an auxiliary-based stereoselective route to such compounds. (C) 2000 Elsevier Science Ltd.

Stereo- and enantioselective routes to functionalised cyclohexenes via heterodiene cycloadditions of 6-oxocyclohexene-1-carbaldehydes with ketene acetals

Various substituted cyclohexenes related to α-cyclocitral have been prepared using the heterodiene cycloadditions of 2-formyl-4,4-dimethyl-2- cyclohexen-1-one 4 with ketene acetals as the pivotal step. The key intermediates are accessible in homochiral form via an auxiliary-based sequence in which a C2-symmetric ketene acetal derived from 1,2-bis(2- methylphenyl)ethane-1,2-diol 2a serves as the 2π component. The diol 2a can be recovered in optically pure form.