832-80-4

Usage

Uses

Used in Photoaffinity Labeling:
9-Diazo-9H-fluorene is used as a photoaffinity labeling reagent for identifying and characterizing biomolecules, such as proteins and nucleic acids, by covalently attaching a reactive diazo group to the target molecule upon exposure to light.
Used in Preparation of Fluorinated Aromatic Compounds:
9-Diazo-9H-fluorene is used as a precursor in the synthesis of fluorinated aromatic compounds, which have applications in various fields, including pharmaceuticals, agrochemicals, and materials science.
Used in Organic Synthesis:
9-Diazo-9H-fluorene is used as a building block in organic synthesis for the preparation of various organic compounds, such as dyes, pigments, and polymers.
Used in Chemical Research:
9-Diazo-9H-fluorene is used as a research tool in chemical research to study the properties and reactions of diazo compounds and to develop new synthetic methods and applications.
It is important to handle 9-Diazo-9H-fluorene with caution due to its potential hazardous properties.

InChI:InChI=1/C13H8N2/c14-15-13-11-7-3-1-5-9(11)10-6-2-4-8-12(10)13/h1-8H

Upstream product

• 13629-22-6 fluoren-9-ylidene-hydrazine 
• 486-25-9 9-fluorenone 
• 525-03-1 9-aminofluorene 
• 141-52-6 sodium ethanolate 
• 71-43-2 benzene 
• 52341-51-2 N'-(9H-fluoren-9-ylidene)-4-methylbenzenesulfonohydrazide 
• 24040-37-7 9-azido-9H-fluorene 
• 830-72-8 9H-fluorene-9-thione 
• 1940-57-4 9H-fluoren-9-yl bromide 
• 82222-58-0 Fluorenone 2,4,6-triisopropylbenzenesulphonyl hydrazone 
• 2157-52-0 9-fluorenone oxime 

Downstream Products

• 3120-03-4 3-phenyl-spiro[3-aza-bicyclo[3.1.0]hexane-6,9'-fluorene]-2,4-dione 
• 81123-57-1 (+/-)-5'-phenyl-(3'ar,6'ac)-3'a,6'a-dihydro-spiro[fluorene-9,3'-pyrrolo[3,4-c]pyrazole]-4',6'-dione 
• 3191-81-9 3-p-tolyl-spiro[3-aza-bicyclo[3.1.0]hexane-6,9'-fluorene]-2,4-dione 
• 81123-62-8 1-methyl-3-phenyl-spiro[3-aza-bicyclo[3.1.0]hexane-6,9'-fluorene]-2,4-dione 
• 103404-07-5 4-fluoren-9-ylidene-2,6-diphenyl-4H-pyran 
• 857789-02-7 (9-chloro-fluoren-9-yl)-(2-nitro-phenyl)-sulfide 
• 28114-92-3 (9H-fluoren-9-yl) (phenyl) sulfane 
• 110423-43-3 3-phenyl-1⁽²⁾H-dibenz[e,g]indazole 
• 31859-87-7 N-phenyl-9H-fluoren-9-amine 
• 4535-09-5 N-phenyl-fluorenoneimine-N-oxide 
• 751-35-9 9-fluorenone triphenylphosphazine 
• 124107-84-2 6-phenoxy-quinoline-3,4-dione-3-fluoren-9-ylidenehydrazone 
• 861373-41-3 (diethyl-phenyl-phosphoranylidene)-fluoren-9-ylidene-hydrazine 
• 63767-42-0 phenyl-(3-phenyl-spiro[cyclopropane-1,9'-fluoren]-2-yl)-ketone 

Relevant academic research and scientific papers

Synthesis of extended chromophores derived from 5,5-dimethyloxyluciferin by barton-kellogg methodology

An approach to the synthesis of modified methyl ether-protected dimethyloxyluciferin derivatives is presented, focusing on the enlargement of the π-system. This was achieved by introducing an alkene bridge at the 4-position of the thiazoline moiety to lin

Mechanochromism, Twisted/Folded Structure Determination, and Derivatization of (N-Phenylfluorenylidene)acridane

(N-Phenylfluorenylidene)acridane (Ph-FA) compounds with electron-withdrawing and -donating substituents (H, MeO, Ph, NO2, Br, F) at the para position of the phenyl group were successfully synthesized by Barton–Kellogg reactions of N-aryl thioacridones and diazofluorene. By using the substituent on the nitrogen atom to alter the electronic properties, both the folded and twisted conformers of p-NO2-C6H4-FA could be crystallographically characterized, which enabled the charge transfer from the electron-donating acridane moiety to the electron-accepting fluorenylidene moiety to be understood. Ground-state mechanochromism, thermochromism, vapochromism, and proton-induced chromism were demonstrated between the folded and twisted conformations of the conformers. Protonation and chemical oxidation of Ph-FA gave two stable acridinium compounds, namely, the fluorenylacridinium and acridinium radical cations. The present study will contribute to the development of functional dyes and organic semiconductors.

Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical–Radical Cross-Coupling

The first visible-light-induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical–radical cross-coupling step was achieved. This method provided a mild, step-economical and redox-neutral route to privileged two different fluorinated difunctionalized allyl compounds. The utility of this method is illustrated by late-stage modification of medically important molecules.

Efficient synthesis of ferrocifens and other ferrocenyl-substituted ethylenes: Via a 'sulfur approach'

Stable and non-odorous alkyl ferrocenyl thioketones react with bis(4-methoxyphenyl)diazomethane according to the 'two-fold extrusion' reaction principles, and tetrasubstituted ethylenes obtained thereby can be demethylated to give (Fc,2OH)-ferrocifens in good yields. The method offers an alternative approach to this class of medically relevant compounds. A similar protocol with alkyl ferrocenyl thioketones and selected diaryldiazomethanes leads to ferrocenyl-substituted ethylenes including dibenzofulvenes. These products are of potential interest for electrochemical and photophysical studies.

Continuous Flow Synthesis and Purification of Aryldiazomethanes through Hydrazone Fragmentation

Electron-rich diazo compounds, such as aryldiazomethanes, are powerful reagents for the synthesis of complex structures, but the risks associated with their toxicity and instability often limit their use. Flow chemistry techniques make these issues avoidable, as the hazardous intermediate can be used as it is produced, avoiding accumulation and handling. Unfortunately, the produced stream is often contaminated with other reagents and by-products, making it incompatible with many applications, especially in catalysis. Herein is reported a metal-free continuous flow method for the production of aryldiazomethane solutions in a non-coordinating solvent from easily prepared, bench-stable sulfonylhydrazones. All by-products are removed by an in-line aqueous wash, leaving a clean, base-free diazo stream. Three successful sensitive metal-catalyzed transformations demonstrated the value of the method.

New applications of hetaryl thioketones for the synthesis of hetaryl-substituted ethenes via 'two-fold extrusion reaction'

A series of aryl/hetaryl thioketones was applied for the reactions with aryl/hetaryldiazomethanes yielding, after elimination of N2, the corresponding thiiranes. The relatively unstable dihetaryldiazomethanes were generated in situ from the corresponding hydrazones by oxidation with DMSO. The obtained thiiranes were converted into tetraaryl/hetaryl-substituted ethenes in good yields by desulfurization performed with tris(diethylamino)phosphine ((Et2N)3P).

PROTEIN DERIVATIZATION TO ENDOW CELL PENETRATION

Methods and reagents for enhancing cellular uptake of a cargo molecule by covalently bonding optionally-substituted fluorenyl groups to the cargo molecules, where cellular uptake includes at least partial uptake into the cytosol. Useful fluorenylation reagents include those of formula: and salts thereof where variables are as defined. Cargo molecules include peptides and proteins. Also provided are fluorenylated cargo molecules, including fluorenylated peptides and proteins.

gem-Difluoroolefination of Diazo Compounds with TMSCF3 or TMSCF2Br: Transition-Metal-Free Cross-Coupling of Two Carbene Precursors

A new olefination protocol for transition-metal-free cross-coupling of two carbene fragments arising from two different sources, namely, a nonfluorinated carbene fragment resulting from a diazo compound and a difluorocarbene fragment derived from Ruppert-Prakash reagent (TMSCF3) or TMSCF2Br, has been developed. This gem-difluoroolefination proceeds through the direct nucleophilic addition of diazo compounds to difluorocarbene followed by elimination of N2. Compared to previously reported Cu-catalyzed gem-difluoroolefination of diazo compounds with TMSCF3, which possesses a narrow substrate scope due to a demanding requirement on the reactivity of diazo compounds and in-situ-generated CuCF3, this transition-metal-free protocol affords a general and efficient approach to various disubstituted 1,1-difluoroalkenes, including difluoroacrylates, diaryldifluoroolefins, as well as arylalkyldifluoroolefins. In view of the ready availability of diazo compounds and difluorocarbene reagents and versatile transformations of 1,1-difluoroalkenes, this new gem-difluoroolefination method is expected to find wide applications in organic synthesis.

Fluorogenic Strain-Promoted Alkyne-Diazo Cycloadditions

Fluorogenic reactions, in which non- or weakly fluorescent reagents produce highly fluorescent products, are attractive for detecting a broad range of compounds in the fields of bioconjugation and material sciences. Herein, we report that a dibenzocyclooctyne derivative modified with a cyclopropenone moiety (Fl-DIBO) can undergo fast strain-promoted cycloaddition reactions under catalyst-free conditions with azides, nitrones, nitrile oxides, as well as mono- and disubstituted diazo-derivatives. Although the reaction with nitrile oxides, nitrones, and disubstituted diazo compounds gave cycloadducts with low quantum yield, monosubstituted diazo reagents produced 1H-pyrazole derivatives that exhibited an approximately 160-fold fluorescence enhancement over Fl-DIBO combined with a greater than 10 000-fold increase in brightness. Concluding from quantum chemical calculations, fluorescence quenching of 3H-pyrazoles, which are formed by reaction with disubstituted diazo-derivatives, is likely due to the presence of energetically low-lying (n,π?) states. The fluorogenic probe Fl-DIBO was successfully employed for the labeling of diazo-tagged proteins without detectable background signal. Diazo-derivatives are emerging as attractive reporters for the labeling of biomolecules, and the studies presented herein demonstrate that Fl-DIBO can be employed for visualizing such biomolecules without the need for probe washout.

Tuning the rotation rate of light-driven molecular motors

Overcrowded alkenes are among the most promising artificial molecular motors because of their ability to undergo repetitive light-driven unidirectional rotary motion around the central C=C bond. The exceptional features of these molecules render them highly useful for a number of applications in nanotechnology. Many of these applications, however, would benefit from higher rotation rates. To this end, a new molecular motor was designed, and the isomerization processes were studied in detail. The new motor comprises a fluorene lower half and a five-membered-ring upper half; the upper-half ring is fused to a p-xylyl moiety and bears a tert-butyl group at the stereogenic center. The kinetics of the thermal isomerization was studied by low-temperature UV-vis spectroscopy as well as by transient absorption spectroscopy at room temperature. These studies revealed that the tert-butyl and p-xylyl groups in the five-membered-ring upper half may be introduced simultaneously in the molecular design to achieve an acceleration of the rotation rate of the molecular motor that is larger than the acceleration obtained by using either one of the two groups individually. Furthermore, the new molecular motor retains unidirectional rotation while showing remarkably high photostationary states.