135075-91-1

Upstream product

• 100124-06-9 4-dibenzofurylboronic acid 
• 696-62-8 para-iodoanisole 
• 82102-37-2 9-methyl-9H-fluorene-9-carbonyl chloride 
• 66283-60-1 dibenzofuran carboxylic acid chloride 
• 100-66-3 methoxybenzene 

Relevant academic research and scientific papers

An air-tolerant approach to the carbonylative suzuki-miyaura coupling: Applications in isotope labeling

Carbonylative Suzuki-Miyaura coupling conditions have been developed that proceed without the exclusion of oxygen and in the presence of nondegassed and nondried solvents. By adapting the method to a two-chamber setup, the direct handling of carbon monoxide, produced from stable CO precursors, is avoided. The protocol afforded the desired benzophenones with excellent functional group tolerance and in good yields. Substituting the CO precursor, in the CO-producing chamber, with its carbon-13 labeled version generated the corresponding carbon-13 labeled benzophenones. Finally, the developed system was applied in the synthesis and isotope labeling of two pharmaceuticals, nordazepam and Tricor.

Positional Reactivity of Dibenzofuran in Electrophilic Substitutions

Isomer distributions of dibenzofuran (DBF) in Friedel-Crafts acylations, Friedel-Crafts alkylations, and nitrations have been determined.The 2- and 3-positions of DBF represents most of the total reactivity.However, the ratio of 2- to 3-isomers greatly varied, depending on the nature of the electrophile.The positional reactivities have been found to be in the following sequence: 2- > 3- > 1- > 4-positions for Friedel-Crafts acylations, Friedel-Crafts benzylations, and nitrations with alkyl nitrate/Lewis acid or nitronium tetrafluoroborate.The ratios for acylations varied over a range from 13.1 to 2.9, while for benzylations and nitrations from 2.0 to 1.0.In contrast, for nitrations of DBF with nitric acid a different reactivity order was found: 3- > 2- > 1- > 4-, with the ratio varying from 0.8 to 0.03 depending on the nature of solvents used.The selectivity for the 3-substitution increased with increase in nitronium ion-like character of nitrating reagents.In particular, nitration with nitric acid in dichloromethane gave mostly 3-nitro-DBF (95percent of the four possible isomeric mixture).The charge-transfer nitration with tetranitromethane under the UV irradiation has shown a similar isomer distribution to that in nitration with nitric acid.The MNDO calculations predicts that the late transition-state model (by ?-complex) favors reactions at the 2-position while the early transition-state model (by HOMO electron density) leads to the 3-substitution.