16939-15-4

Upstream product

• 769-57-3 α,β,β-trimethylstyrene 
• 18476-73-8 (3-methylbuta-1,3-dien-2-yl)benzene 
• 30318-99-1 3-bromo-4-methylthiophene 
• 98-80-6 phenylboronic acid 
• 616-44-4 3-Methylthiophene 
• 768-32-1 trimethylphenylsilane 
• 98-09-9 benzenesulfonyl chloride 
• 591-50-4 iodobenzene 
• 29290-99-1 2-methyl-3-phenylbut-1-en-3-ol 

Downstream Products

• 126954-02-7 2-(α-Carbomethoxy-α-trifluoroacetamidotrifluoroethyl)-3-methyl-4-phenylthiophene 
• 83125-20-6 2,5-dibromo-3-methyl-4-phenylthiophene 
• 215377-86-9 3-methyl-2,4-diphenylthiophene 

Relevant academic research and scientific papers

Redox-Divergent Construction of (Dihydro)thiophenes with DMSO

Thiophene-based rings are one of the most widely used building blocks for the synthesis of sulfur-containing molecules. Inspired by the redox diversity of these features in nature, we demonstrate herein a redox-divergent construction of dihydrothiophenes, thiophenes, and bromothiophenes from the respective readily available allylic alcohols, dimethyl sulfoxide (DMSO), and HBr. The redox-divergent selectivity could be manipulated mainly by controlling the dosage of DMSO and HBr. Mechanistic studies suggest that DMSO simultaneously acts as an oxidant and a sulfur donor. The synthetic potentials of the products as platform molecules were also demonstrated by various derivatizations, including the preparation of bioactive and functional molecules.

Characterization of heterogeneous aryl-Pd(ii)-oxo clusters as active species for C-H arylation

C-H arylation with heterogeneous palladium was investigated. The surface oxidation of Pd nanoparticles with a hypervalent iodine reagent, [Ph2I]BF4, resulted in the generation of Pd(ii)-aryl-oxo clusters, which were characterized as the crucial intermediate.

Palladium-catalyzed dehydrogenative coupling of cyclic enones with thiophenes: A rapid access to β-heteroarylated cyclic enones

Dehydrogenative coupling of cyclic enones with heteroarenes has been a longstanding challenge because of the competitive ketone dehydrogenation and conjugated addition. Herein, a dehydrogenative coupling reaction of cyclic enones of different sizes with substituted thiophenes to construct β-thienyl cyclic enone compounds through palladium-catalyzed C-H functionalization under mild reaction conditions is reported. Simple substituted thiophenes with different functional groups can be directly introduced into cyclic enones with predominant regioselectivity at the α position of thiophene moieties and excellent functional group tolerance. Further molecular transformations of the coupling products to synthetically useful meta-heteroarylated phenol derivatives have also been demonstrated.

Ligand-free Suzuki-Miyaura coupling using ruthenium(0) nanoparticles and a continuously irradiating microwave system

We developed a conceptually and methodologically novel ruthenium(0) nanoparticle catalyst, sulfur-modified Au-supported ruthenium nanoparticles (SARu). SARu is easily prepared through a three-step procedure involving simultaneous in situ metal nanoparticle and nanospace organization. This unique method does not require any conventional preformed template to immobilize and stabilize metal nanoparticles. SARu is an ideal ruthenium catalyst for liquid-phase combinatorial synthesis because it repeatedly catalyzes ligand-free Suzuki-Miyaura coupling of aryl halides, including aryl chlorides, with arylboronic acids with low Ru leaching. Physical analysis of SARu showed that the active species in these reactions were ruthenium (0) nanoparticles with a size of 1-3 nm. Also, we developed a continuously irradiating microwave methodology, which can first time discriminate the heating effect and the microwave effect in microwave experiments.

Selective β-Arylation of Thiophenes with Aryl Iodides Catalyzed by Dinuclear Palladium Carboxylate Complexes

Novel dinuclear palladium complexes bearing acetoxy ligands were synthesized and characterized by X-ray crystal analysis. The complexes were utilized for the arylation of 2-ethylthiophene with iodobenzene to give ethylphenylthiophenes with high β selectiv

Pd/C as a catalyst for completely regioselective c=h functionalization of thiophenes under mild conditions

The completely C3-selective arylation of thiophenes and benzo[b]thiophenes was achieved by using Pd/C as a heterogeneous catalyst without ligands or additives under mild reaction conditions. The practicability of this transformation is demonstrated by notable functional group tolerance and the insensitivity of the reaction to H2O and air. This method is also applicable to nitrogen- and oxygen-containing heterocycles, yielding the corresponding C2-arylated products. Three-phase tests along with Hg-poisoning and hot-filtration tests suggest that the catalytically active species is heterogeneous in nature. I+ can do better! Pd/C can be used without ligands or additives to catalyze the completely C3-selective arylation of diversely substituted thiophenes and benzo[b]thiophenes under mild reaction conditions. The physical nature of the catalytic species was investigated and the mechanism was studied. Relative rate data generated in a "robustness screen" were used to design a complex substrate that undergoes highly chemoselective sequential functionalization. Copyright

Benzenesulfonyl chlorides: New reagents for access to alternative regioisomers in palladium-catalysed direct arylations of thiophenes

The palladium-catalysed coupling of benzenesulfonyl chlorides with thiophene derivatives allows regioselective access to β-arylated thiophenes. The reaction proceeds with easily accessible catalyst, base and substrates, without oxidant or ligand and tolerates a variety of substituents on both the benzene and thiophene moieties.

A highly active catalytic system for Suzuki-Miyaura cross-coupling reactions of aryl and heteroaryl chlorides in water

An easily available Pd(OAc)2/(2-mesitylindenyl) dicyclohexylphosphine/Me(octyl)3N+Cl-/K 3PO4·3H2O catalytic system was developed and it shows high catalytic activity in the Suzuki-Miyaura cross-coupling reaction of a diverse array of aryl and heteroaryl chlorides in water. Notably, this catalytic system also works with ultra-low loading of the catalyst with high turnover numbers.

Pd-catalyzed β-selective direct C-H bond arylation of thiophenes with aryltrimethylsilanes

Direct arylation of thiophenes and benzothiophenes with aryltrimethylsilanes was effectively catalyzed by PdCl2(MeCN) 2 in the presence of CuCl2 as an oxidant. The reaction preferentially occurred at the β-position of both

Synthetic inhibitors of cytochrome P-450 2A6: Inhibitory activity, difference spectra, mechanism of inhibition, and protein cocrystallization

A series of 3-heteroaromatic analogues of nicotine were synthesized to delineate structural and mechanistic requirements for selectively inhibiting human cytochrome P450 (CYP) 2A6. Thiophene, substituted thiophene, furan, substituted furan, acetylene, imidazole, substituted imidazole, thiazole, pyrazole, substituted pyrazole, and aliphatic and isoxazol moieties were used to replace the N-methylpyrrolidine ring of nicotine. A number of potent inhibitors were identified, and several exhibited high selectivity for CYP2A6 relative to CYP2E1, -3A4, -2B6, -2C9, -2C19, and -2D6. The majority of these inhibitors elicited type II difference spectra indicating the formation of a coordinate covalent bond to the heme iron. The majority of inhibitors were reversible inhibitors although several mechanism-based inactivators were identified. Most of the inhibitors were also relatively metabolically stable. X-ray crystal structures of CYP2A6 cocrystallized with three furan analogues bearing methanamino side chains indicated that the amine side chain coordinated to the heme iron. The pyridyl moiety was positioned to accept a hydrogen bond from Asn297, and all three inhibitors exhibited orthogonal aromatic-aromatic interactions with protein side chains. For comparison, the cocrystal structure of 4,4′-dipyridyl disulfide was also obtained and showed that the pyridine moiety could assume a different orientation than that observed for the 3-heteroaromatic pyridines examined. For the 3-heteroromatic pyridines, N-methyl and N,N-dimethyl amino groups increased the apparent Ki and distorted helix I of the protein. Substitution of a phenyl ring for the pyridyl ring also increased the apparent Ki, which is likely to reflect the loss of the hydrogen bonding interaction with Asn297. In contrast, inhibitory potency for other P450s was increased, and the selectivity of the phenyl analogues for CYP2A6 was decreased relative to the pyridyl compounds. The results suggest that inhibitors that compliment the active site features of CYP2A6 can exhibit significant selectivity for CYP2A6 relative to other human liver drug-metabolizing P450s.