40460-91-1

Upstream product

• 117125-64-1 3-(4-Bromo-phenyl)-3-methyl-oxirane-2-carbonitrile 
• 69217-52-3 t-butyl β-methyl-β-(p-bromophenyl)glycidate 
• 99-90-1 para-bromoacetophenone 
• 105-39-5 chloroacetic acid ethyl ester 
• 2039-82-9 1-bromo-4-ethenyl-benzene 
• 201230-82-2 carbon monoxide 
• 81310-74-9 4-bromo-α-methyl-benzeneethanol 
• 83636-46-8 methyl 2-(4-bromophenyl)propanoate 
• 41841-16-1 (4-bromo-phenyl)-acetic acid methyl ester 
• 589-87-7 1,4-bromoiodobenzene 
• 107-18-6 allyl alcohol 
• 6888-79-5 4-bromo-α-methylstyrene 
• 80909-78-0 p-bromo-α-methylstyrene oxide 
• 111914-79-5 (+/-)-2-(4-bromophenyl)propionic acid ethyl ester 

Downstream Products

• 40460-74-0 [(E)-2-(4-Bromo-phenyl)-propenyl]-(4-methoxy-phenyl)-amine 
• 40460-69-3 4-Brom-hydratropaaldehyd-benzylimin 
• 1236832-04-4 5-methyl-5-(4-bromophenyl)-6-(4-methoxyphenylamino)bicyclo[2.2.2]octan-2-one 
• 1233867-67-8 4-(4-bromophenyl)-5-butyl-4-methyl-2-cyclohexen-1-one 
• 1233867-63-4 4-(4-bromophenyl)-4,5-dimethyl-2-cyclohexen-1-one 
• 1296698-90-2 (S)-di-tert-butyl 1-(2-(4-bromophenyl)-1-oxopropan-2-yl)hydrazine-1,2-dicarboxylate 
• 1431642-29-3 C₁₇H₂₁BrN₂O₃ 
• 1304668-78-7 (R)-di-tert-butyl 1-(2-(4-bromophenyl)-1-oxo-propan-2-yl)hydrazine-1,2-dicarboxylate 
• 1245633-09-3 diethyl 1-(1-oxo-2-(4-bromophenyl)propan-2-yl)hydrazine-1,2-dicarboxylate 

Relevant academic research and scientific papers

Chemical space exploration of oxetanes

This paper focuses on new derivatives bearing an oxetane group to extend accessible chemical space for further identification of kinase inhibitors. The ability to modulate kinase activity represents an important therapeutic strategy for the treatment of h

Reduced flexibility analogs of analgesic and cognition enhancing α-tropanyl esters

A series of semirigid analogs of compounds 1 and 2, two potent analgesics and cognition enhancers, have been synthesized and tested for antinociceptive activity (hot plate test) and for muscarinic affinity (binding in rat cerebral cortex). They were found to be in a general less potent than the reference compounds; only one of them (22) shows a good affinity for the muscarinic receptor and an antinociceptive efficacy comparable with those of the reference compounds. At a dose of 30 mg/kg 22 is also able to reverse the amnesic effect of dicyclomine. Since the analgesic effect of these compounds is affected by the 5-HT4 antagonist SDZ 205557, the possible role of this receptor is discussed.

Cobalt-Catalyzed Aerobic Oxidative Cleavage of Alkyl Aldehydes: Synthesis of Ketones, Esters, Amides, and α-Ketoamides

A widely applicable approach was developed to synthesize ketones, esters, amides via the oxidative C?C bond cleavage of readily available alkyl aldehydes. Green and abundant molecular oxygen (O2) was used as the oxidant, and base metals (cobalt and copper) were used as the catalysts. This strategy can be extended to the one-pot synthesis of ketones from primary alcohols and α-ketoamides from aldehydes.

An Asymmetric SN2 Dynamic Kinetic Resolution

The SN2 reaction exhibits the classic Walden inversion, indicative of the stereospecific backside attack of the nucleophile on the stereogenic center. Observation of the inversion of the stereocenter provides evidence for an SN2-type displacement. However, this maxim is contingent on substitution proceeding on a discrete stereocenter. Here we report an SN2 reaction that leads to enantioenrichment of product despite starting from a racemic mixture of starting material. The enantioconvergent reaction proceeds through a dynamic Walden cycle, involving an equilibrating mixture of enantiomers, initiated by a chiral aminocatalyst and terminated by a stereoselective SN2 reaction at a tertiary carbon to provide a quaternary carbon stereocenter. A combination of computational, kinetic, and empirical studies elucidates the multifaceted role of the chiral organocatalyst to provide a model example of the Curtin-Hammett principle. These examples challenge the notion of enantioenriched products exclusively arising from predefined stereocenters when operating through an SN2 mechanism. Based on these principles, examples are included to highlight the generality of the mechanism. We anticipate the asymmetric SN2 dynamic kinetic resolution to be used for a variety of future reactions.

Synthesis of rac-ɑ-aryl propionaldehydes via branched-selective hydroformylation of terminal arylalkenes using water-soluble Rh-PNP catalyst

This work detailed the preparation of a class of water-soluble PNP ligands that differed by the nature of the substitute on phenyl ring of ligands. These ligands were incorporated into water-soluble rhodium-PNP complex catalysts that were used to regioselective hydroformylation of a series of terminal arylalkenes, providing efficient access to rac-α-aryl propionaldehydes in good to excellent yield (up to 97%) and branched-regioselectivity (up to 40:1 b/l ratio). Furthermore, gram-scale and diverse synthetic transformation demonstrated synthetic application of this methodology for non-steroidal antiinflammatory drugs.

Highly Enantioselective Synthesis of Propargyl Amide with Vicinal Stereocenters through Ir-Catalyzed Hydroalkynylation

Chiral propargyl amines are valuable synthetic intermediates for the preparation of biologically active compounds and functionalized amines. Catalytic methods to access propargyl amines containing vicinal stereocenters with high diastereoselectivity are particularly rare. We report an unprecedented strategy for the synthesis of enantioenriched propargyl amines with two stereogenic centres. An iridium complex, ligated by a phosphoramidite ligand, catalyzes the hydroalkynylation of β,β-disubstituted enamides to afford propargyl amides in a highly regio-, diastereo-, and enantioselective fashion. Stereodivergent synthesis of all four possible stereoisomers was achieved using this strategy.

Binuclear Pd(I)-Pd(I) Catalysis Assisted by Iodide Ligands for Selective Hydroformylation of Alkenes and Alkynes

Since its discovery in 1938, hydroformylation has been thoroughly investigated and broadly applied in industry (>107 metric ton yearly). However, the ability to precisely control its regioselectivity with well-established Rh- or Co-catalysts has thus far proven elusive, thereby limiting access to many synthetically valuable aldehydes. Pd-catalysts represent an appealing alternative, yet their use remains sparse due to undesired side-processes. Here, we report a highly selective and exceptionally active catalyst system that is driven by a novel activation strategy and features a unique Pd(I)-Pd(I) mechanism, involving an iodide-assisted binuclear step to release the product. This method enables β-selective hydroformylation of a large range of alkenes and alkynes, including sensitive starting materials. Its utility is demonstrated in the synthesis of antiobesity drug Rimonabant and anti-HIV agent PNU-32945. In a broader context, the new mechanistic understanding enables the development of other carbonylation reactions of high importance to chemical industry.

Highly Enantioselective Catalytic Kinetic Resolution of α-Branched Aldehydes through Formal Cycloaddition with Homophthalic Anhydrides

A new catalytic methodology was developed to promote an efficient one-pot kinetic resolution of racemic aldehydes with selectivity (s*) of up to 91 (99:1 d.r., >99 % ee) in a cycloaddition reaction with enolizable anhydrides to afford dihydroisocoumarin products (a core prevalent in natural products and molecules of medicinal interest) containing three contiguous stereocentres.

Synthesis of tetra-pincer nickel(ii) and palladium(ii) complexes of resorcin[4]arene-octophosphinite [Res(OPR2)8] and rhodium-catalyzed regioselective hydroformylation reaction

The condensation reaction of resorcinol with pentanal yielded resorcin[4]arene 1 which on bromination using N-bromosuccinimide at room temperature produced tetra-bromide derivative 2. The reactions of 2 with chlorodiphenylphosphine and o-phenylenephosphoro-chloridite yielded octaphosphinite 3 (hereafter referred to as octaphos) and octaphosphite 4, respectively. The reactions of 3 with Ni(COD)2 or Pd2(dba)3·CHCl3 in appropriate molar ratios yielded tetra-pincer complexes 5 and 6, respectively. The structures of both the complexes were established by single crystal X-ray diffraction studies. The resorcin[4]arene backbone adopts a boat structure in these complexes. Typically, the Rh-catalyzed hydroformylation of styrene prevalently delivers a branched (b) chiral aldehyde. A unique resorcin[4]arene skeleton based octaphos 3 was employed in the Rh-catalyzed hydroformylation of styrene. The hydroformylation of styrene with a metal to ligand ratio of 1:1 (M:L) was found to be regioselective, producing a linear (l) aldehyde as a major product with 100% conversion in 3 h. The l:b ratio surprisingly increased when the ortho positions of styrene were populated by methyl and chloro substituents. The hydroformylation of p-nitro styrene triggered a remarkably high linear:branched aldehyde ratio of 2.4 (71% linear aldehyde) despite its electron withdrawing nature. The highest linear selectivity of 97% (l:b ratio 27.8) was achieved in the case of 2,4,6-trimethylstyrene.

Mild Iridium-Catalysed Isomerization of Epoxides. Computational Insights and Application to the Synthesis of β-Alkyl Amines

The isomerization of epoxides to aldehydes using the readily available Crabtree's reagent is described. The aldehydes were transformed into synthetically useful amines by a one-pot reductive amination using pyrrolidine as imine-formation catalyst. The reactions worked with low catalyst loadings in very mild conditions. The procedure is operationally simple and tolerates a wide range of functional groups. A DFT study of its mechanism is presented showing that the isomerization takes place via an iridium hydride mechanism with a low energy barrier, in agreement with the mild reaction conditions. (Figure presented.).