64583-10-4

Upstream product

• 38693-94-6 (E)-4-<2-(4-fluorophenyl)ethenyl>phenol 
• 77-78-1 dimethyl sulfate 
• 1145-93-3 diethyl 4-methoxybenzylphosphonate 
• 459-57-4 4-fluorobenzaldehyde 
• 2746-25-0 p-Methoxybenzyl bromide 
• 637-69-4 4-Methoxystyrene 
• 352-13-6 4-flourophenylmagnesium bromide 
• 462-06-6 fluorobenzene 
• 943-89-5 (E)-3-(4-methoxyphenyl)acrylic acid 
• 352-34-1 4-fluoro-1-iodobenzene 
• 6303-59-9 (E)-4-(2-bromo-vinyl)-anisole 
• 93296-09-4 4-methoxyphenylzinc chloride 
• 405-99-2 para-fluorostyrene 
• 104-92-7 1-bromo-4-methoxy-benzene 

Downstream Products

• 24941-76-2 1-fluoro-4-(4-methoxyphenethyl)benzene 
• 39769-24-9 (E)-4-fluoro-4'-methoxystilbene 
• 1588534-23-9 C₂₈H₂₀F₂O₂ 
• 38693-94-6 (E)-4-<2-(4-fluorophenyl)ethenyl>phenol 
• 1608492-53-0 (2R,3S,4R,5S)-3,4-bis(4-fluorophenyl)-2,5-bis(4-methoxyphenyl)tetrahydrofuran 

Relevant academic research and scientific papers

Palladacycles: Efficient new catalysts for the heck vinylation of aryl halides

Cyclopalladated complexes of the general formula [Pd2(μ-L)2(P-C)2] (L = bridging ligand, e.g. OAc, Cl, Br, I; P-C = cyclometallated P donor, e.g. o-CH2C6H4P(o-Tol)2 or o-CH2C6H2(CH3)2-P(Mes)2) are highly efficient catalysts for the Heck vinylation of aryl halides. The isolated complexes are easily accessible from palladium(II) acetate by spontaneous metallation of ortho-methyl-substituted arylphosphines. They display improved activity and stability compared to conventional catalyst mixtures (e.g. [Pd(OAc)2] +nPPh3), and also exhibit a higher stability towards air than conventional Pd(o)-based systems (e.g. [Pd(P-Ph3)4]). Turnover numbers (TON) of up to 1000000 and turnover frequencies (TOF) in the range of 5000-20000 are achieved in catalytic coupling reactions of aryl bromides. Even technically interesting aryl chlorides undergo the Hock reaction (TON = 600-40000) if promoting salts are added to the catalyst ((NBu4)Br, LiBr). The new structural type for catalysts is compared to palladacycles formed in situ from mixtures of [Pd(OAc)2] + P(o-tolyl)3 and the established [Pd(OAc)2] +nPPh3 system. The scope of the new C-C coupling catalysts is outlined for the vinylation of aryl halides by the use of different mono- and disubstituted olefins. Mechanistic consequences for the Hack reaction in general are discussed.

Stereospecific Iron-Catalyzed Carbon (sp2)-Carbon (sp2) Cross-Coupling of Aryllithium with Vinyl Halides

We present herein an efficient synthetic protocol involving iron-catalyzed cross-coupling of organolithium compounds with vinyl halides as key coupling partners. More than 30 examples were obtained with moderate to good yields and high stereoselectivities. The practicality of this method is evidenced by a gram-scale synthesis. In addition, a preliminary mechanistic investigation was also performed.

Illuminating Stannylation

We have developed photoboosted stannylation reactions of terminal alkynes (linear-selective hydrostannylation) and fluoroarenes (defluorostannylation), in which the stannyl anion is photoexcited to an excited triplet (T1) stannyl diradical species. This u

Transition-Metal-Free Matsuda-Heck Type Cross-Coupling and Mechanistic Evidence for a Radical Mechanism

The Matsuda-Heck reaction, usually performed with palladium catalysts, can be carried out under transition-metal-free conditions in the presence of a KOtBu/DMF couple. This system allows the selective and direct synthesis of stilbenes from aryldiazonium salts under mild temperature (20 °C). Mechanistic studies suggest a radical pathway in which the DMF acts as the initiator of the overall process.

One-Pot Intermolecular Reductive Cross-Coupling of Deactivated Aldehydes to Unsymmetrically 1,2-Disubstituted Alkenes

The phospha-Peterson reaction between a lithiated secondary phosphane, MesP(Li)TMS, and an aldehyde affords Mes-phosphaalkenes which, upon methanol addition and P-oxidation, react with a second carbonyl compound site specifically to produce unsymmetric alkenes. The E/Z selectivity of the one-pot cross coupling is largely determined by the electronic nature of the aryl substituent of the first aldehyde, with electron-donating groups giving rise to increased amounts of Z-alkenes.

An Interrupted Pummerer/Nickel-Catalysed Cross-Coupling Sequence

An interrupted Pummerer/nickel-catalysed cross-coupling strategy has been developed and used in the elaboration of styrenes. The operationally simple method can be carried out as a one-pot process, involves the direct formation of stable alkenyl sulfonium salt intermediates, utilises a commercially available sulfoxide, catalyst, and ligand, operates at ambient temperature, accommodates sp-, sp2-, and sp3-hybridised organozinc coupling partners, and delivers functionalised styrene products in high yields over two steps. An interrupted Pummerer/cyclisation approach has also been used to access carbo- and heterocyclic alkenyl sulfonium salts for cross-coupling.

Activation of anti-oxidant Nrf2 signaling by substituted trans stilbenes

Nrf2, which is a member of the cap'n’ collar family of transcription factors, is a major regulator of phase II detoxification and anti-oxidant genes as well as anti-inflammatory and neuroprotective genes. The importance of inflammation and oxidative stress in many chronic diseases supports the concept that activation of anti-oxidant Nrf2 signaling may have therapeutic potential. A number of Nrf2 activators have entered into clinical trials. Nrf2 exists in the cytosol in complex with its binding partner Keap1, which is a thiol-rich redox-sensing protein. In response to oxidative and electrophilic stress, select cysteine residues of Keap1 are modified, which locks Keap1 in the Nrf2-Keap1 complex and allows newly synthesized Nrf2 to enter the nucleus. Numerous Nrf2-activating chemicals, including a number of natural products, are electrophiles that modify Keap1, often by Michael addition, leading to activation of Nrf2. One concern with the design of Nrf2 activators that are electrophilic covalent modifiers of Keap1 is the issue of selectivity. In the present study, substituted trans stilbenes were identified as activators of Nrf2. These activators of Nrf2 are not highly electrophilic and therefore are unlikely to activate Nrf2 through covalent modification of Keap1. Dose-response studies demonstrated that a range of substituents on either ring of the trans stilbenes, especially fluorine and methoxy substituents, influenced not only the sensitivity to activation, reflected in EC50values, but also the extent of activation, which suggests that multiple mechanisms are involved in the activation of Nrf2. The stilbene backbone appears to be a privileged scaffold for development of a new class of Nrf2 activators.

Synthesis and tyrosinase inhibition activity of trans-stilbene derivatives

Synthesis of a focussed library of trans-stilbene compounds through Wittig and other base catalysed condensation reactions is presented. The synthesized stilbenes were screened for their inhibitory potential against murine tyrosinase activity to explore the structure activity relationship (SAR). Presence of electron withdrawing group (-CN) at the double bond and hydroxyl group or halogen atom especially at para-position on the aromatic rings was found to significantly elevate the inhibitory activity. Among all the compounds screened, compounds 2, 6, 8, 10, 11, 15 and 21 were found to exhibit appreciable inhibitory activity. Compound 21 ((E)-2,3-bis(4-Hydroxyphenyl)acryonitrile) was found to be the most active with an IC50 value of 5.06 μM which is less than half of the value 10.78 μM observed for resveratrol (common standard used in murine tyrosinase activity studies) under similar conditions. The results obtained from the present study reveal structural/functional group sensitivity for the tyrosinase inhibitory activity of stilbenoid moieties and are expected to be very helpful for the design and synthesis of novel, selective and effective tyrosinase inhibitors.

Preparation of Vinyl Arenes by Nickel-Catalyzed Reductive Coupling of Aryl Halides with Vinyl Bromides

This work emphasizes the synthesis of substituted vinyl arenes by reductive coupling of aryl halides with vinyl bromides under mild and easy-to-operate nickel-catalyzed reaction conditions. A broad range of aryl halides, including heteroaromatics, and vinyl bromides were employed to yielding products in moderate to excellent yields with high functional-group tolerance. The nickel-catalytic system displays good chemoselectivity between the two C(sp2)-halide coupling partners, thus demonstrating a mechanistic pathway distinct from other stepwise protocols.

The aromatic production of olefins

PROBLEM TO BE SOLVED: To provide a method for efficiently producing aromatic olefins useful for various functional chemicals.SOLUTION: Aromatic olefins are produced by reaction of an aromatic compound with an epoxide or aldehyde in the presence of a solid