685544-23-4

Upstream product

• 108-94-1 cyclohexanone 
• 586-96-9 Nitrosobenzene 
• 627106-80-3 (7β,11β)-3,3-dimethyl-7,11-diphenyl-2,4-dioxaspiro[5.5]undecane-1,5,9-trione 

Downstream Products

• 62445-01-6 (1R,3R)-cyclohexane-1,2,3-triol 

Relevant academic research and scientific papers

Novel organic catalysts for the direct enantioselective α-oxidation of carbonyl compounds

The proline-derived N-sulfonylcarboxamide-catalyzed direct enantioselective α-oxidation of ketones and aldehydes with nitrosobenzene is presented. The reactions proceed smoothly furnishing the corresponding α-aminoxylated compounds in good yields with up to >99% ee. The proline-derived N-sulfonylcarboxamides were also found to be excellent catalysts for the direct enantioselective nitroso Diels-Alder-type reaction between nitrosobenzene and α,β-unsaturated cyclic ketones yielding the corresponding bicyclic Diels-Alder adduct products with up to >99% ee. The proline-derived N-sulfonylcarboxamides represent a readily available and highly modular novel type of organic catalyst.

Direct amino acid-catalyzed asymmetric desymmetrization of meso-compounds: Tandem aminoxylation/O-N bond heterolysis reactions

(Chemical Equation Presented) A practical organocatalytic process for the synthesis of optically active, highly substituted α-hydroxy-ketones was achieved through asymmetric desymmetrization (ADS) of prochiral ketones. The ADS and O-N bond reduction reaction of prochiral ketone with nitrosobenzene in the presence of a catalytic amount of chiral amine or amino acid produced the tandem ADS/O-N bond reduced products as single diastereomers with good yields and excellent enantiomeric excesses.

Direct catalytic enantioselective α-aminoxylation of ketones: A stereoselective synthesis of α-hydroxy and α,α′- dihydroxy ketones

Proline-catalyzed reactions between unmodified ketones and nitrosobenzene proceed with excellent diastereo- and enantioselectivities to provide protected α-hydroxy and α,α′-dihydroxy ketones [Eq. (1)]. Such compounds with chiral α-hydroxy carbonyl units are crucial in natural product synthesis.

The direct catalytic asymmetric α-aminooxylation reaction: Development of stereoselective routes to 1,2-diols and 1,2-amino alcohols and density functional calculations

Proline-catalyzed direct asymmetric α-aminooxylation of ketones and aldehydes is described. The proline-catalyzed reactions between unmodified ketones or aldehydes and nitrosobenzene proceeded with excellent diastereo- and enantioselectivities. In all cases tested, the corresponding products were isolated with > 95% ees. Methyl alkyl ketones were regiospecifically oxidized at the methylene carbon atom to afford enantiomerically pure α-aminooxylated ketones. In addition, cyclic ketones could be α,α′-dioxidized with remarkably high selectivity, furnishing the corresponding diaminooxylated ketones with > 99% ees. The reaction mechanism of the proline-catalyzed direct asymmetric α-aminooxylation was investigated, and we performed density functional theory (DFT) calculations in order to investigate the nature of the plausible transition states further. We also screened other organocatalysts for the asymmetric α-oxidation reaction and found that several proline derivatives were also able to catalyze the transformation with excellent enantioselectivities. Moreover, stereoselective routes for the synthesis of monoprotected vicinal diols and hydroxyketones were found. In addition, short routes for the direct preparation of enantiomerically pure epoxides and 1,2-amino alcohols are presented. The direct catalytic α-oxidation is also a novel route for the stereoselective preparation of β-adrenoreceptor antagonists.

Direct proline-catalyzed asymmetric α-aminoxylation of aldehydes and ketones

The direct proline-catalyzed asymmetric α-aminoxylation of aldehydes and ketones has been developed using nitrosobenzene as an oxygen source, affording α-anilinoxy-aldehydes and -ketones with excellent enantioselectivity. Reaction conditions have been optimized, and low temperature (-20 °C) was found to be a key for the successful α-aminoxylation of aldehydes, while slow addition of nitrosobenzene is essential for that of ketones. The scope of the reaction is presented.