79644-47-6Relevant academic research and scientific papers
7b-Methyl-7bH-cyclopentindene, an Unsubstituted Tricyclic Aromatic Annulene
Gilchrist, Thomas L.,Tuddenham, David,McCague, Raymond,Moody, Christopher J.,Rees, Charles W.
, p. 657 - 658 (1981)
The aromatic tricyclic annulene (4) has been synthesised by bis-decarbonylation of the dialdehyde (3); on heating (4) rearranged into the 2aH-isomer (6).
A New Synthesis of the Tricyclic Annulene 7b-Methyl-7bH-cyclopentindene
Lidert, Zev,Rees, Charles W.
, p. 499 - 500 (1982)
In a new versatile synthesis of the tricyclic annulene, 7b-methyl-7bH-cyclopentindene, the third ring is formed by an intramolecular aldol condensation rather than a cycloaddition reaction.
Phenol-Keto Tautomerism in Tricyclic Annulenes; Preparation and Properties of 7b-Methyl-2a,7b-Dihydrocyclopentinden-2-(2H)-one
McCague, Raymond,Moody, Christoffer J.,Rees, Charles W.
, p. 622 - 624 (1982)
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
McCague, Raymond,Moody, Christopher J.,Rees, Charles W.
, p. 175 - 182 (2007/10/02)
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.
Tricyclic Annulenes. Part 2. Synthesis of 7b-Methyl-7bH-cyclopentindene
McCague, Raymond,Moody, Christopher J.,Rees, Charles W.
, p. 165 - 174 (2007/10/02)
Four routes have been developed to the tricyclic annulene, 7b-methyl-7bH-cyclopentindene (1), starting from the diester (2a), the tricyclic nitrile (6), or the tricyclic ketone (9).The best overall procedure involves the ketones (9a) and (15).The
Dimethyl 7b-Methyl-7bH-cyclopentindene-1,2-dicarboxylate. A New 10?-Electron Aromatic System
Gilchrist, Thomas L.,Rees, Charles W.,Tuddenham, David
, p. 83 - 86 (2007/10/02)
The title compound (8a) is formed by the acid-catalysed elimination of methanol from the cycloadduct (7) of 3-methoxy-3a-methyl-3aH-indene and dimethyl acetylenedicarboxylate.Its physical and chemical properties are consistent with a 10?-electron aromatic periphery which sustanis a diamagnetic ring current.It is photochemically and thermally stable, but rearranges slowly in boiling xylene to the isomer (11) by a methyl shift.With copper(II) nitrate and acetic anhydride, it gives a mixture of mononitro-substitution products.Preliminary experiments show that decarbonylation of the dialdehyde (8e) with tris(triphenylphosphine)rhodium(I) chloride provides a route to the unsubstituted tricyclic annulene (8f).
Electrophilic Substitution in a Tricyclic Annulene
McCague, Raymond,Moody, Christopher J.,Rees, Charles W.
, p. 497 - 499 (2007/10/02)
Electrophilic aromatic substitution reactions of the annulene (4) are reported, together with an improved method for its preparation.
