4810-10-0

Upstream product

• 1120-72-5 2-Methylcyclopentanone 
• 6303-82-8 1-phenylhexane-1,5-dione 
• 59321-58-3 1-Phenyl-4-hexen-1-ol 
• 20472-04-2 1-chloro-2-methylcyclopentene 
• 591-51-5 phenyllithium 
• 108-86-1 bromobenzene 
• 93-55-0 1-phenyl-propan-1-one 
• 22865-01-6 (R,R)-1-phenyl-2-methylcyclopentanol 
• 22865-14-1 (R,S)-1-phenyl-2-methylcyclopentanol 
• 19960-95-3 2-methyl-1-phenylcyclopentanol 

Downstream Products

• 104912-29-0 1,2-epoxy-1-methyl-2-phenyl-cyclopentane 
• 1560-02-7 cis 1-methyl-2-phenylcyclopentane 
• 35729-02-3 1-Phenyl-5-methyl-6-exo-hydroxymethyl<3,1,0>-hexan 
• 35729-02-3 6-endo-(hydroxymethyl)-5-methyl-1-phenylbicyclo<3.1.0>hexane 
• 6303-82-8 1-phenylhexane-1,5-dione 
• 142942-55-0 1-(4-cyanophenyl)-2-methyl-1-phenylcyclopentane 
• 1560-02-7 trans 1-methyl-2-phenylcyclopentane 

Relevant academic research and scientific papers

Hydrogen Bonding Networks Enable Br?nsted Acid-Catalyzed Carbonyl-Olefin Metathesis**

Synthetic chemists have learned to mimic nature in using hydrogen bonds and other weak interactions to dictate the spatial arrangement of reaction substrates and to stabilize transition states to enable highly efficient and selective reactions. The activation of a catalyst molecule itself by hydrogen-bonding networks, in order to enhance its catalytic activity to achieve a desired reaction outcome, is less explored in organic synthesis, despite being a commonly found phenomenon in nature. Herein, we show our investigation into this underexplored area by studying the promotion of carbonyl-olefin metathesis reactions by hydrogen-bonding-assisted Br?nsted acid catalysis, using hexafluoroisopropanol (HFIP) solvent in combination with para-toluenesulfonic acid (pTSA). Our experimental and computational mechanistic studies reveal not only an interesting role of HFIP solvent in assisting pTSA Br?nsted acid catalyst, but also insightful knowledge about the current limitations of the carbonyl-olefin metathesis reaction.

Carbonyl-Olefin Metathesis Catalyzed by Molecular Iodine

The carbonyl-olefin metathesis reaction could facilitate rapid functional group interconversion and allow construction of complicated organic structures. Herein, we demonstrate that elemental iodine, a very simple catalyst, can efficiently promote this chemical transformation under mild reaction conditions. Our mechanistic studies revealed intriguing aspects of the activation mode via molecular iodine and the iodonium ion that could change the previously established perception of catalyst and substrate design for the carbonyl-olefin metathesis reaction.

Tropylium-promoted carbonyl-olefin metathesis reactions

The carbonyl-olefin metathesis (COM) reaction is a highly valuable chemical transformation in a broad range of applications. However, its scope is much less explored compared to analogous olefin-olefin metathesis reactions. Herein we demonstrate the use of tropylium ion as a new effective organic Lewis acid catalyst for both intramolecular and intermolecular COM and new ring-opening metathesis reactions. This represents a significant improvement in substrate scope from recently reported developments in this field.

Gold-catalyzed deoxygenative Nazarov cyclization of 2,4-dien-1-als for stereoselective synthesis of highly substituted cyclopentenes

Treatment of 2,4-dien-1-als with allylsilanes and PPh3AuSbF 6 (3 mol %) led to formation of 1,4-bis(allyl)cyclopentenyl products; this gold catalyst is superior to commonly used Lewis acids according to catalyst screening. Such gold-catalyzed deoxygenative cyclizations are compatible with various oxygen-, amine-, sulfur-, hydrogen-, and carbon-based nucleophiles. The value of this new catalysis is demonstrated by the diverse annulations of 2,4-dien-1-als with electron-rich alkenes and arenes, providing an easy access to complicated cyclopentenyl frameworks. Structural analysis of annulation products reveals evidence for the participation of Nazarov cyclization. This deoxygenative cyclization is extensible to a tandem intramolecular cyclization/nucleophilic addition cascade, giving polycyclic carbo- or oxacyclic compounds with controlled stereochemistry. This new gold catalysis is applied to a short synthesis of natural compounds of the brazilane family, including brazilane, O-trimethyl-, and O-tetramethyl brazilane.

Mechanisms of solvolytic elimination reactions of tertiary substrates: Stereospecific 1,2-elimination reactions

Solvolysis of (R,S)-1-chloro-1-(fluoren-9-yl)-2-methylcyclopentane (1-Cl) or the analogous 3,5-dinitrobenzoate ester 1-DNB in largely aqueous solutions yields alkenes 1-(fluoren-9-yl)-2-methylcyclopentene (4) and 1-(fluoren-9-yl)-5-methylcyclopentene (5)

The importance of conformation in the reactivity of radical cations. Changing configuration at saturated carbon centres

Irradiation of an acetonitrile solution of cis-1-methyl-2-phenylcyclopentane (1b cis); 1,4-dicyanobenzene (2), an electron-accepting photosensitizer; and 2,4,6-collidine (3), a nonnucleophilic base, leads to configurational isomerization of the cyclopenta