31680-20-3

Upstream product

• 908094-04-2 phenyldiazomethane 
• 614-47-1 1,3-diphenyl-propen-3-one 
• 3471-08-7 (2SR,3SR)-2,3-diphenylcyclopropanecarboxylic acid 
• 98-87-3 benzylidene dichloride 
• 94-41-7 benzalacetophenone 
• 75-18-3 dimethylsulfide 
• 27992-27-4 sodium 2-benzylidene-1-tosylhydrazin-1-ide 
• 100-44-7 benzyl chloride 
• 6921-34-2 benzylmagnesium chloride 

Relevant academic research and scientific papers

Reductive Cyclopropanations Catalyzed by Dinuclear Nickel Complexes

Dinuclear Ni complexes supported by naphthyridine-diimine (NDI) ligands catalyze the reductive cyclopropanation of alkenes with CH2Cl2 as the methylene source. The use of mild terminal reductants (Zn or Et2Zn) confers significant functional-group tolerance, and the catalyst accommodates structurally and electronically diverse alkenes. Mononickel catalysts bearing related N chelates afford comparatively low cyclopropane yields (≤20 %). These results constitute an entry into catalytic carbene transformations from oxidized methylene precursors.

Enhanced diastereoselectivity via confinement: Diastereoselective photoisomerization of 2,3-diphenyl-1-benzoylcyclopropane derivatives within zeolites

Photochemistry of optically pure trans-2,3-diphenyl-1-benzoylcyclopropane has been examined in isotropic solution and within zeolites. Results suggest that it isomerizes by cleavage of either the C1-C2 or C1-C3

Application of chiral sulfides to catalytic asymmetric aziridination and cyclopropanation with in situ generation of the diazo compound

Imines and alkenes can be converted into the corresponding aziridines and cyclopropanes (see scheme, PTC = phase-transfer catalyst, Ts = toluene-4-sulfonyl) in good yield with moderate to high d.r. and high ee values using tosylhydrazone salts with catalytic quantities of chiral sulfide (5-20 mol%) and metal catalyst (1 mol%). The process is particularly suited to the synthesis of conformationally locked cyclopropyl amino acids, which can now be prepared in only three steps from commercially available material in 100% ee.

Catalytic cyclopropanation of electron deficient alkenes mediated by chiral and achiral sulfides: Scope and limitations in reactions involving phenyldiazomethane and ethyl diazoacetate

Phenyldiazomethane reacts with electron deficient alkenes in the presence of catalytic amounts of transition metal catalyst [Rh2(OAc)4 was better than Cu(acac)2] and catalytic amounts of sulfide to give cyclopropanes. Pentamethylene sulfide was found to be superior to tetrahydrothiophene and the optimum solvent was toluene. Under these optimised conditions a range of enones were cyclopropanated in high yields. Cyclic enones and acrylates were not successful in this process. The use of the chiral 1,3-oxathiane derived from camphorsulfonyl chloride in 2 steps in this process furnished cyclopropanes in good yield and very high enantiomeric excess (>97% ee). The absolute stereochemistry of cyclopropane 10 was proven by X-ray analysis and the origin of the stereochemical induction has been rationalised. Extension of this work to include diazoesters was partially successful. Again pentamethylene sulfide was found to be superior to tetrahydrothiophene, but this time both Rh2(OAc)4 and Cu(acac)2 were found to be equally effective. Enones, fumarates and unsaturated nitro compounds worked well but simple acrylates and unsaturated aldehydes were not effective substrates. Control experiments were conducted in which the stabilised ylide was isolated and reacted with the less successful substrates and, whilst unsaturated aldehydes still gave low yields, simple acrylates gave high yields of the corresponding cyclopropane. The use of the chiral 1,3-oxathiane was not successful with these more stable diazo compounds.

Cyclopropanation reactions of enones with lithiated sulfoximines: Application to the asymmetric synthesis of chiral cyclopropanes

Stabilized lithiated sulfoximines 2 and 9 undergo highly diastereoselective Michael reactions with acyclic enones under kinetically controlled conditions. At rt the initially formed anionic Michael adducts undergo intramolecular displacement of the sulfonimidoyl group, with inversion of stereochemistry at the carbon bearing the nucleofuge, to give cyclopropanes. Lithiated sulfoximines derived from S-alkyl sulfoximines give mixtures of 1,2- and 1,4-adducts with enones mider kinetically controlled conditions. However, at rt the 1,2-adducts are in equilibrium with their corresponding 1,4-adducts. The 1,4-adducts are formed in a highly diastereoselective manner and are rapidly converted to diastereomerically pure cyclopropanes in good to excellent yields. Optically active versions of these sulfoximines give cyclopropanes in high enantiomeric purities.

Process for the preparation of an oxirane, azirdine or cyclopropane

A process for the preparation of an oxirane, aziridine or cyclopropane of formula (I) wherein, X is oxygen, NR4 or CHR5 ; R1 is hydrogen, alkyl, aryl, heteroaromatic, heterocyclic or cycloalkyl; R2 is hydrogen, alkyl, aryl, heteroaromatic, CO2 R8, CHR14 NHR13, heterocyclic or cycloalkyl; or R1 and R2 join together to form a cycloalkyl ring; R3 is hydrogen, alkyl, aryl, heteroaromatic, CO2 R8, R83 Sn, CONR8 R9 or trimethylsilyl; R4 and R5 are, independently, alkyl, cycloalkyl, aryl, heteroaromatic, SO2 R8, SO3 R8, COR8, CO2 R8, CONR8 R9 or CN, or R4 can also be P(O)(aryl)2 ; R8 and R9 are independently alkyl, aryl or arylalkyl; R13 and R14 are independently hydrogen, alkyl or aryl; the process comprising reacting a mixture of a compound of formula (II), wherein R1, R2 and X are as defined above, and a sulphide of formula SR6 R7, wherein R6 and R7 are independently alkyl, aryl or heteroaomatic, or R6 and R7 join together to form a cycloalkyl ring which optionally includes an additional heteroatom, with either (i) a metallocarbon obtainable by reacting an alkylmetal with a methane derivative of formula CHR3 X'X", wherein R3 is as defined above, and X' and X" are independently, a leaving group, or (ii) a metallocarbon obtainable by reacting a compound of formula (III), (wherein R3 may not be hydrogen) with a suitable organometallic or inorganic reagent.