111718-47-9

Upstream product

• 75414-38-9 (6S)-4-benzoyloxy-6-benzoyloxymethyl-2H-pyran-3(6H)-one 
• 67-64-1 acetone 
• 1451079-91-6 ((2S,5S)-5-allyl-5-hydroxy-4-oxo-tetrahydro-2H-pyran-2-yl)methyl benzoate 
• 1451079-87-0 (2S)-(5-allyl-4-tert-butyldimethylsilyloxy-3,6-dihydro-2H-pyran-2-yl)methyl benzoate 
• 1451079-79-0 (2S)-(5-allyl-4-tert-butyldimethylsilyloxy-3,6-dihydro-2H-pyran-2-yl)methanol 
• 1451079-77-8 (-)-(2S)-ethyl 5-allyl-4-tert-butyldimethylsilyloxy-3,6-dihydro-2H-pyran-2-carboxylate 
• 1451079-76-7 2-tert-butyldimethylsilyloxy-3-methylenehexa-1,5-diene 
• 52358-87-9 3-methylenehex-5-en-2-one 
• 14125-75-8 2,3,4,6-tetra-O-benzoyl-D-hydroxyglucal 
• 82569-81-1 1,5-anhydro-3,4,6-tri-O-benzoyl-D-fructose oxime 
• 75414-32-3 1,5-anhydro-3,4,6-tri-O-benzoyl-D-fructose 
• 67863-40-5 lithium isopropenolate 

Relevant academic research and scientific papers

Asymmetric synthesis of (-)-bissetone via a highly enantioselective hetero-Diels-Alder reaction

We demonstrate a new approach for the asymmetric synthesis of bissetone. The key reaction is the highly enantioselective hetero-Diels-Alder cycloaddition of triene 3 with ethyl glyoxylate catalyzed by readily available BINOL-Ti complexes. The HDA cycloadduct 4 was then transformed in five steps into O-protected bissetone (8) and its C5-epimer in good yield.

Expedient conversion of d-glucose into 1,5-anhydro-d-fructose and into single stereogenic-center dihydropyranones, suitable six-carbon scaffolds for concise syntheses of the soft-coral constituents (-)-bissetone and (-)-palythazine

High-yielding protocols are described to convert d-glucose-via hydroxylaminolysis of its hydroxyglucal esters, followed by deoximination and β-elimination of acid-into dihydropyranone building blocks with a single stereogenic center. Their versatility as enantiopure six-carbon scaffolds is highlighted by excellent regio- and stereocontrol in a variety of addition reactions and by their straightforward use as building blocks for the concise syntheses of the soft-coral constituents bissetone and palythazine in enantiopure form, thereby proving their absolute configuration. Moreover, several procedures are detailed to convert hydroxyglucal esters into 1,5-anhydro-d-fructose, their parent sugar, the direct low-temperature de-O-acylation being the most suitable for preparative purposes, as long as its access via enzymatic degradation of starch is not implemented on an appreciable scale.