42523-32-0

Upstream product

• 35450-36-3 methyl 2-bromo-5-methoxybenzoate 
• 89466-08-0 2-hydroxyphenyl boronic acid 
• 552-16-9 ortho-nitrobenzoic acid 
• 533-58-4 2-Iodophenol 
• 5720-07-0 4-methoxyphenylboronic acid 
• 201230-82-2 carbon monoxide 
• 21849-91-2 2-(4-methoxyphenyl)phenol 
• 95-56-7 2-hydroxybromobenzene 
• 934691-48-2 4-methoxy-[1,1'-biphenyl]-2-carbaldehyde 
• 7507-86-0 2-bromo-5-methoxy-benzaldehyde 
• 98-80-6 phenylboronic acid 
• 2905-82-0 methyl 5-methoxy-2-hydroxybenzoate 
• 2612-02-4 5-methoxysalicylic acid 
• 345924-12-1 5-methoxy-2-trifluoromethanesulfonyloxy benzoic acid methyl ester 

Relevant academic research and scientific papers

Cerium Ammonium Nitrate-Mediated Access to Biaryl Lactones: Substrate Scopes and Mechanism Studies

Herein we described an access to biaryl lactones from ortho-aryl benzoic acids via intramolecular O-H/C-H oxidative coupling with the commonly used cerium ammonium nitrate (CAN) as the one-electron oxidant under a thermal condition. The radical interrupting experiment suggested a radical process, while the kinetic isotope effect (KIE) showed that the C-H cleavage likely was not involved in the rate-determining step. Competitive reactions, especially the strikingly different ρ values of Hammett equations, indicated that the reaction rate was more sensitive to the electronic properties on the aryl moiety rather than the carboxylic moiety, which corresponded to the first single electron transfer (SET) step. In addition, the quite negative ρ values (-4.7) of the aryl moiety unveiled the remarkable electrophilic nature of the second intramolecular radical addition process, which was also consistent with product yields and regioselectivity. Moreover, control experiments disclosed that the single electron in the third step was also transferred to CeIV instead of molecular oxygen. Besides, the possible role of co-solvents trifluoroethanol (TFE) and its influences on the CeIV species were discussed. This work elucidated the possible mechanism by proposing the step that had more effects on the total reaction rate and the species that was responsible for the last single electron transfer.

Intramolecular Aromatic C-H Acyloxylation Enabled by Iron Photocatalysis

A mild and efficient protocol for the intramolecular aromatic C-H oxygenation of 2-biphenylcarboxylic acids has been achieved via iron photocatalysis. The 2-biphenylcarboxylic acids with a diverse array of substituents at both phenyl rings could furnish the oxygenation products in good to excellent yields. We speculate that the aryl carboxylate-iron(III) complexes should generate the aroyloxy radicals and iron(II) upon visible light irradiation.

Microwave-assisted cyclization under mildly basic conditions: Synthesis of 6 h -benzo [c] chromen-6-ones and their 7,8,9,10-tetrahydro analogues

Aryl 2-bromobenzoates and aryl 2-bromocyclohex-1-enecarboxylates are cyclized by microwave irradiation in dimethylformamide in the presence of K2CO3 to give the corresponding 6H-benzo[c]chromen-6-ones and their 7,8,9,10-tetrahydro analogues, respectively, in 50-72% yields. Aryl 3-bromoacrylates are also converted into 2H-chromen-2-ones under the employed conditions.

Vitamin Catalysis: Direct, Photocatalytic Synthesis of Benzocoumarins via (-)-Riboflavin-Mediated Electron Transfer

An operationally simple protocol is disclosed to facilitate entry to benzo-3,4-coumarins directly from biaryl carboxylic acids without the need for substrate prefunctionalization. Complementary to classic lactonization strategies, this disconnection relies on the oxidation competence of photoactivated (-)-riboflavin (vitamin B2) to generate the heterocyclic core via photoinduced single electron transfer. Collectively, the inexpensive nature of the catalyst, ease of execution, and absence of external metal additives are a convincing endorsement for the incorporation of simple vitamins in contemporary catalysis.

Synthesis of dibenzopyranones and pyrazolobenzopyranones through copper(0)/Selectfluor system-catalyzed double C[sbnd]H activation/oxygen insertion of 2-arylbenzaldehydes and 5-arylpyrazole-4-carbaldehydes

A mild and efficient protocol for the synthesis of dibenzopyranones and pyrazolobenzopyranones was developed involving a copper(0)/Selectfluor system-catalyzed double C[sbnd]H activation/oxygen insertion of 2-arylbenzaldehydes and 5-arylpyrazole-4-carbaldehydes. Preliminary mechanistic studies suggest that both water and dioxygen act as the oxygen source in the formation of pyranone scaffolds.

KOtBu mediated efficient approach for the synthesis of fused heterocycles via intramolecular O-/N-arylations

A novel and efficient methodology for the synthesis of 6H-benzo[c]chromenes, 6H-benzo[c]chromen-6-ones, carbazoles, dibenzofurans, dibenzooxepins has been developed. The reaction goes through intramolecular O-/N-arylations with sp2C-Br bonds via typical SNAr pathway in presence of potassium-tert-butoxide base.

Copper catalyzed room temperature lactonization of aromatic C-H bond: A novel and efficient approach for the synthesis of dibenzopyranones

We have developed a novel and efficient methodology for the intramolecular aryl C-H oxidative lactonization of 2-arylbenzaldehyde using a low-cost CuCl catalyst and TBHP as the oxidant at room temperature. We applied the methodology to the synthesis of a series of dibenzopyranones.

NIS-mediated oxidative lactonization of 2-arylbenzoic acids for the synthesis of dibenzopyranones under metal-free conditions

A series of dibenzopyranones were synthesized from 2-arylbenzoic acids by a radical oxidative cyclization procedure mediated by N-iodosuccinimide (NIS). The methodology is distinguished by its practicality in terms of its wide substrate scope, good functi

Synthesis of dibenzopyranones through palladium-catalyzed directed C-H activation/carbonylation of 2-arylphenols

Dibenzopyranones were synthesized by a palladium-catalyzed phenol-directed C-H activation/carbonylation of 2-phenylphenol derivatives in the presence of CO. Pd(OAc)2 was used as a catalyst and Cu(OAc)2 as a catalytic oxidant in the presence of air. Copyright

Ruthenium-catalyzed carbonylative C-H cyclization of 2-arylphenols: A novel synthetic route to 6 H-dibenzo[b,d]pyran-6-ones

Catalytic carbonylative C-H cyclization of 2-arylphenols can be achieved in the presence of a ruthenium-based catalytic system. The process proceeds efficiently under balloon pressure of CO and produces variously substituted 6H-dibenzo[b,d]pyran-6-one compounds, typically in good to high yields. Functional groups such as the alkoxycarbonyl and acetyl groups as well as halogen atoms (F, Cl, and Br) are well tolerated during the reaction.