32346-66-0

Upstream product

• 502-44-3 hexahydro-2H-oxepin-2-one 
• 73504-72-0 phenyl(tetrahydro-2H-pyran-2-yl)methanone 
• 108-86-1 bromobenzene 
• 17851-49-9 5-hydroxypentyl phenyl ketone 
• 347376-10-7 trans-6-oxo-6-phenylhex-4-enal 
• 34879-53-3 cis-3a,5,6,6a-Tetrahydro-3-phenyl-4H-cyclopentisoxazole 
• 285-67-6 Cyclopentene oxide 
• 100-47-0 benzonitrile 
• 87258-30-8 6-oxo-6-phenylhexanal 
• 58074-39-8 3-phenyl-3a,5,6,6a-tetrahydrocyclopentaisoxazoline 

Relevant academic research and scientific papers

Photomediated ring contraction of saturated heterocycles

Saturated heterocycles are found in numerous therapeutics and bioactive natural products and are abundant in many medicinal and agrochemical compound libraries. To access new chemical space and function, many methods for functionalization on the periphery of these structures have been developed. Comparatively fewer methods are known for restructuring their core framework. Herein, we describe a visible light-mediated ring contraction of a-acylated saturated heterocycles. This unconventional transformation is orthogonal to traditional ring contractions, challenging the paradigm for diversification of heterocycles including piperidine, morpholine, thiane, tetrahydropyran, and tetrahydroisoquinoline derivatives. The success of this Norrish type II variant rests on reactivity differences between photoreactive ketone groups in specific chemical environments. This strategy was applied to late-stage remodeling of pharmaceutical derivatives, peptides, and sugars.

Cyclopentane Formation from Flexible Precursors Using Samarium(II) Reagents

Three efficient methods for five-membered ring carbocycle synthesis have been developed from simple starting materials using samarium(II) reagents. A Reformatsky aldol reaction proceeded efficiently with samarium(II) iodide using lithium bromide as an additive. A new intramolecular alkylation of a samarium enolate was realized with a pendant sulfonate ester leaving group. Pinacol cyclization of a simple diketone was also demonstrated giving a diol product in high stereoselectivity. A promising lead result has been established demonstrating enantioselectivity in a chiral ligand controlled Reformatsky aldol reaction.

Borinic Acid/Halide Co-catalyzed Semipinacol Rearrangements of 2,3-Epoxy Alcohols

A new mode of catalysis of the semipinacol rearrangement of 2,3-epoxy alcohols is described. In combination with a halide salt additive, diarylborinic acids promote a Type II rearrangement that occurs with net retention of configuration. This unusual stereochemical outcome is consistent with a mechanism involving regioselective ring opening of the epoxy alcohol by halide, followed by rearrangement of the resulting halohydrin-derived borinic ester. The protocol is applicable to a range of substrates, enabling ring contractions and expansions as well as stereospecific syntheses of acyclic β-hydroxycarbonyl compounds.

Titanocene-promoted intermolecular couplings of epoxides with nitriles. An easy access to β-hydroxyketones

(Chemical Equation Presented) Radical couplings of epoxides and nitriles mediated by Cp2TiCl provide a diastereoselective route to the synthesis of β-hydroxyketones. The conditions of this "aldol- like" reaction are mild enough to avoid the dehydration of the β-hydroxyketone. The scope of the coupling reaction with functionalized and tetrasubstituted epoxides has been studied. The radical character of the coupling reactions is demonstrated.

TBD-catalyzed direct 5- and 6-enolexo aldolization of ketoaldehydes

Treatment of unfunctionalized acyclic ketoaldehydes with a catalytic amount of 1,5,7-triazabicyclo[4.4.0]dec-5-ene induces a direct intramolecular 5- and 6-enolexo aldolization, furnishing 2-ketocyclopentanols and 2-ketocyclohexanols in good-to-excellent yields. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.

Reductive generation of enolates from enones using elemental hydrogen: Catalytic C-C bond formation under hydrogenative conditions

Exposure of enones to elemental hydrogen in the presence of a Rh(I) catalyst enables reductive enolate generation, as evidenced by electrophilic trapping of the enolate by appendant and exogenous aldehyde partners. The significance of these findings resides in the ability to regioselectivity generate and transform transition metal enolates under catalytic conditions that circumvent formation of stoichiometric byproducts. Copyright

TRANSFORMATIONS OF N-METHYL-4,5-DIHYDROISOXAZOLIUM METHYLSULPHATES

Reactions of N-methyl-4,5-dihydroisoxazolium methylsulphates with: H2O, H2O2 or KMnO4, NaNO2, NEt3, NaCN, NaN3 yielded respectively: β-methylaminoxyketones, β-hydroxyketones, β-(N-nitroso)methylaminoxyketones, a mixture of N-methyl-2,5-dihydroisoxazole an

Cleavage of Isoxazolines with Tricarbonyltris(acetonitrile)molybdenum and Silica Gel. Synthesis of 1-(2-Oxoalkyl)cyclopropanols from Isoxazoline-5-spirocyclopropanes

An efficient synthesis of 1-(2-oxoalkyl)cyclopropanols from isoxazoline-5-spirocyclopropanes by selective N-O cleavage effected by Mo(CO)3(MeCN)3 and silica gel is described.