79644-47-6

Basic information

• Product Name: 7b-methyl-7bH-cyclopenta[cd]indene
• Synonyms: 7b-Methyl-7bH-cyclopent(cd)indene; 7b-Methyl-7bH-cyclopent[cd]indene
• CAS NO: 79644-47-6
• Molecular Formula: C₁₂H₁₀
• Molecular Weight: 154.2078
• Mol File: 79644-47-6.mol
• Article Data: 7

Chemical Properties

• Boiling Point: 360.9°C at 760 mmHg
• Flash Point: 134.7°C
• Density: 1.12g/cm³
• Vapor Pressure: 4.48E-05mmHg at 25°C
• Refractive Index: 1.655
• CAS DataBase Reference: 7b-methyl-7bH-cyclopenta[cd]indene(CAS DataBase Reference)
• NIST Chemistry Reference: 7b-methyl-7bH-cyclopenta[cd]indene(79644-47-6)
• EPA Substance Registry System: 7b-methyl-7bH-cyclopenta[cd]indene(79644-47-6)

Safety Data

• Hazardous Substances Data: 79644-47-6(Hazardous Substances Data)

Upstream product

• 89901-07-5 7b-methyl-7bH-cyclopentindene-2-carbaldehyde 
• 90144-80-2 4a,7b-dihydro-7b-methyl-2aH-cyclopentinden-2a-ol 
• 82946-47-2 2a,7b-dihydro-7b-methyl-2H-cyclopentinden-2-ol 
• 90144-83-5 4a,7b-dihydro-2a-methoxy-7b-methyl-2aH-cyclopentindene 
• 90144-81-3 2a,4a-dibromo-4a,7b-dihydro-7b-methyl-2aH-cyclopentindene 
• 89901-20-2 N-chlorosulphonyl-2,9b-dihydro-9b-methyl-1H-indeno<1,7-cd>azepin-1-one 
• 82939-41-1 2a-methoxy-7b-methyl-1,2a,7a,7b-tetrahydro-2H-cyclopentinden-2-one p-tolylsulphonylhydrazone 
• 79644-46-5 7b-methyl-7bH-cyclopentindene-1,2-dicarbaldehyde 
• 82946-41-6 7b-Methyl-2a,7b-dihydrocyclopentinden-2-(2H)-one 
• 82939-40-0 2a-methoxy-7b-methyl-1,2a,7a,7b-tetrahydro-2H-cyclopentinden-2-one 
• 76051-89-3 3-methoxy-3a-methyl-3aH-indene 
• 89901-05-3 7b-methyl-7bH-cyclopentindene-2-carbonitrile 
• 90144-86-8 2a-hydroxy-7b-methyl-1,2a,7a,7b-tetrahydro-2H-cyclopentinden-2-one 2,4,6-tri-isopropylphenylsulphonylhydrazone 
• 88214-39-5 2a-hydroxy-7b-methyl-1,2a,7a,7b-tetrahydro-2H-cyclopentinden-2-one 

Downstream Products

• 89912-00-5 C₂₈H₂₀N₆O₄ 
• 82939-55-7 7b-methyl-7bH-cyclopentindene-1-carbaldehyde 
• 82939-56-8 7b-methyl-7bH-cyclopentindene-5-carbaldehyde 
• 89901-15-5 7b-methyl-7bH-cyclopentindene-6-carbaldehyde 
• 89901-19-9 7b-Methyl-7bH-cyclopenta[cd]indene-5-sulfonic acid; compound with 2-benzyl-isothiourea 

Relevant articles and documents

7b-Methyl-7bH-cyclopentindene, an Unsubstituted Tricyclic Aromatic Annulene

The aromatic tricyclic annulene (4) has been synthesised by bis-decarbonylation of the dialdehyde (3); on heating (4) rearranged into the 2aH-isomer (6).

Phenol-Keto Tautomerism in Tricyclic Annulenes; Preparation and Properties of 7b-Methyl-2a,7b-Dihydrocyclopentinden-2-(2H)-one

The 2-'phenol' in the tricyclic annulene series appears to exist entirely in the keto form (4); the 'phenolate' anion is readily formed, and can be methylated on oxygen, or on carbon to give isomer (9) exclusively.

Tricyclic annulenes. Part 3. Reactions of 7b-Methyl-7bH-cyclopentindene

The chemical reactions of the tricyclic annulene (1) are described.The annulene is rapidly hydrogenated to give the fully saturated hydrocarbon (2).It undergoes a substitution reaction with electrophiles and has been nitrated, acetylated, formylated, and sulphonated.The preferential sites of attack of electrophiles are C-5 and C-1.Although the annulene (1) does not undergo cycloaddition reaction with tetracyanoethylene, dimethyl acetylenedicarboxylate, or benzyne, it does react with 4-phenyl-1,2,4-triazole-3,5-dione in refluxing 1,2-dimethoxyethane to give the 2:1 adduct (17) and with chlorosulphonyl isocyanate to give the ring-expanded indenoazepine (19).Hydrolysis of (19) gives the amide (20), which shows some antiaromatic character.

Electrophilic Substitution in a Tricyclic Annulene

Electrophilic aromatic substitution reactions of the annulene (4) are reported, together with an improved method for its preparation.