Related Experiment Video
Updated: Jul 12, 2026
06:34
Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides (CHIPS)
Published on: June 20, 2014
Redox-Neutral Weak Chelation-Assisted C-H Functionalization/Annulation via Carbene Insertion: Access to
Priya Patra1, Maniya V Nanjegowda1, Shubhajit Basak1
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India.
Organic Letters
|July 9, 2026
Summary
A new Rh-catalyzed reaction efficiently creates benzo[c]oxaphosphinine oxides from arylphosphonic acid monoesters and diazo compounds. This method offers C-C/C-O bond formation with broad scope and functional group tolerance.
Area of Science:
- Organic Chemistry
- Organometallic Chemistry
- Synthetic Chemistry
Background:
- Arylphosphonic acid derivatives are important in medicinal chemistry and materials science.
- Developing efficient synthetic routes to complex heterocyclic compounds remains a key challenge in organic synthesis.
Purpose of the Study:
- To develop a novel Rh-catalyzed cascade reaction for synthesizing functionalized benzo[c]oxaphosphinine oxides.
- To utilize diazo compounds as carbene surrogates in C-H functionalization reactions.
Main Methods:
- Rhodium(II)-catalyzed C-H functionalization and annulation cascade.
- Employing arylphosphonic acid monoesters and diazo compounds as substrates.
- Optimization of reaction conditions to achieve high yields and selectivity.
Main Results:
- Successful synthesis of functionalized benzo[c]oxaphosphinine oxides.
- Demonstration of C-C and C-O bond formation within a single cascade process.
- Achieved reaction under redox-neutral conditions with high site selectivity.
- Exhibited broad substrate scope and tolerance for diverse functional groups.
Conclusions:
- The developed Rh-catalyzed cascade reaction provides an efficient and versatile method for constructing benzo[c]oxaphosphinine oxides.
- The reaction's practical features, including mild conditions and functional group tolerance, make it valuable for synthetic chemists.
More Related Videos
Related Concept Videos
00:59Reactions at the Benzylic Position: Oxidation and Reduction
The benzylic position describes the position of a carbon atom attached directly to a benzene ring. Benzene by itself does not undergo oxidation. In contrast, the benzylic carbon is quite reactive in the presence of strong oxidizing agents such as KMnO4 or H2CrO4. Therefore, alkylbenzenes are readily oxidized to benzoic acid, irrespective of the type of alkyl groups.
01:13Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
01:11ortho–para-Directing Activators: –CH3, –OH, –NH2, –OCH3
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
01:11Nucleophilic Aromatic Substitution: Elimination–Addition
Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is confirmed through isotopic...
01:15Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
Chlorination and bromination are important classes of electrophilic aromatic substitutions, where benzene reacts with chlorine or bromine in the presence of a Lewis acid catalyst to give halogenated substitution products. A Lewis acid such as aluminium chloride or ferric chloride catalyzes the chlorination, and ferric bromide catalyzes the bromination reactions. During the bromination of alkenes, bromine polarizes and becomes electrophilic. However, in the bromination of benzene, the bromine...