254-04-6

Basic information

• Product Name: 2H-chromene
• Synonyms: 2H-chromene;1,2-Benzopyran;1,2-Chromene;2H-1-Benzopyran;3-Chromene
• CAS NO: 254-04-6
• Molecular Formula: C₉H₈O
• Molecular Weight: 132.16
• Mol File: 254-04-6.mol

Chemical Properties

• Melting Point: <25 °C
• Boiling Point: 204.08°C (rough estimate)
• Flash Point: 79.7°C
• Appearance: /
• Density: 1.0993
• Vapor Pressure: 0.169mmHg at 25°C
• Refractive Index: 1.5869
• CAS DataBase Reference: 2H-chromene(CAS DataBase Reference)
• NIST Chemistry Reference: 2H-chromene(254-04-6)
• EPA Substance Registry System: 2H-chromene(254-04-6)

Safety Data

• Hazardous Substances Data: 254-04-6(Hazardous Substances Data)

Usage

Uses

Used in Pharmaceutical Industry:
2H-chromene is used as a key structural component in the development of various pharmaceutical compounds. Its presence in the molecular structure can influence the biological activity and pharmacological properties of the resulting drug candidates. The heterocyclic ring system of 2H-chromene allows for easy modification and functionalization, making it a versatile building block for designing new drugs with specific therapeutic targets.
Used in Chemical Synthesis:
2H-chromene serves as an important intermediate in the synthesis of more complex organic molecules. Its unique chemical structure allows for various synthetic transformations, such as oxidation, reduction, and substitution reactions. These reactions can lead to the formation of a wide range of chemical products, including natural products, agrochemicals, and other specialty chemicals.
Used in Material Science:
The unique properties of 2H-chromene make it a potential candidate for the development of new materials with specific applications in material science. For example, its ability to form stable complexes with other molecules can be exploited to create novel materials with enhanced properties, such as improved stability, selectivity, or reactivity.
Used in Research and Development:
2H-chromene is also used as a research tool in various scientific fields, including organic chemistry, medicinal chemistry, and biochemistry. Its unique chemical properties and reactivity make it an interesting subject for studying fundamental chemical reactions and exploring new synthetic pathways. Additionally, its potential applications in drug discovery and material science make it a valuable compound for researchers working on the development of new technologies and products.

InChI:InChI=1/C9H8O/c1-2-6-9-8(4-1)5-3-7-10-9/h1-6H,7H2

Upstream product

• 254-03-5 4H-1-benzopyran 
• 122-97-4 3-Phenyl-1-propanol 
• 491-37-2 2,3-dihydro-4H-1-benzopyran-4-one 
• 352-13-6 4-flourophenylmagnesium bromide 
• 25125-40-0 1-(2-(allyloxy)phenyl)-2-(tetrafluoro-λ⁵-boraneyl)diazene 
• 13610-02-1 1-phenoxy-2-propyne 
• 271-58-9 anthranil 
• 30518-54-8 3-bromo-2H-chromene 
• 108-24-7 acetic anhydride 

Downstream Products

• 112128-82-2 trans-4-methoxy-3-phenylchroman 
• 6054-00-8 3-phenyl-2H-benzopyran 
• 92496-19-0 4-Phenyl-4H-1-benzopyran 
• 123373-12-6 (6aS,11aS)-9-Methoxy-6a,11a-dihydro-6H-benzo[4,5]furo[3,2-c]chromen-8-ol 
• 123373-13-7 (6aS,6bR,10aS,10bR)-9-Methoxy-6a,6b,10a,10b-tetrahydro-6H-5-oxa-benzo[a]biphenylene-7,10-dione 
• 108335-31-5 rac-(6aR,11aR)-8-hydroxy-3,9-dimethoxypterocarpan 
• 134453-32-0 (6aS,6bR,10aS,10bR)-9-Methoxy-6a,6b,10a,10b-tetrahydro-6H-5-oxa-benzo[a]biphenylene-7,10-dione 
• 87512-57-0 2-(1-ethylprop-2-enyl)phenol 
• 85960-76-5 (E)-2-pent-1-enylphenol 
• 23619-59-2 (E)-2-propenylphenol 
• 87512-65-0 2-(1-isobutylprop-2-enyl)phenol 
• 1745-81-9 o-Allylphenol 
• 38276-75-4 2-(1-phenylallyl)phenol 
• 100-42-5 styrene 

Relevant articles and documents

Synthesis of 2 h-chromenes via hydrazine-catalyzed ring-closing carbonyl-olefin metathesis

The catalytic ring-closing carbonyl-olefin metathesis (RCCOM) of O-Allyl salicylaldehydes to form 2H-chromenes is described. The method utilizes a [2.2.1]-bicyclic hydrazine catalyst and operates via a [3 + 2]/retro-[3 + 2] metathesis manifold. The nature of the allyl substitution pattern was found to be crucial, with sterically demanding groups such as adamantylidene or diethylidene offering optimal outcomes. A survey of substrate scope is shown along with a discussion of mechanism supported by DFT calculations. Steric pressure arising from syn-pentane minimization of the diethylidene moiety is proposed to facilitate cycloreversion.

Direct access to benzofuro[2,3-: B] quinoline and 6 H -chromeno[3,4- b] quinoline cores through gold-catalyzed annulation of anthranils with arenoxyethynes and aryl propargyl ethers

This work reports a facile annulation of anthranils with aryloxyethynes or aryl propargyl ethers to construct useful benzofuro[2,3-b]quinoline and 6H-chromeno[3,4-b]quinoline frameworks, respectively; these heterocycles are not readily available from literature methods despite their biological significance. This high atom- and step-economy strategy is highlighted by a broad substrate scope. The reaction mechanism is proposed to proceed through sequential cyclizations among the oxyaryl group, gold carbene and benzaldehyde of the α-imino gold carbene intermediates.

Iron-catalysed borylation of arenediazonium salts to give access to arylboron derivatives via aryl(amino)boranes at room temperature

Complementary to previously described Miyaura borylation methods, a new access to boron derivatives via aryl(amino)boranes is described. Direct coupling between aryldiazonium salts and diisopropylaminoborane is catalysed by 0.1% ferrocene leading to the formation of a carbon-boron bond. The obtained aryl(amino)boranes could eventually then be transformed into boronic acids, boronates or borates. Copyright

Palladium-catalyzed cross-coupling reaction of secondary benzylic bromides with grignard reagents

"Chemical Equation Presented" A mild palladium-catalyzed Kumada-Corriu reaction of secondary benzylic bromides with aryl and alkenyl Grignard reagents has been developed. In the presence of the Xantphos ligand, the undesired β-elimination pathway Is minimized, affording the corresponding cross-coupling products In acceptable to good yields. The reaction proceeds with inversion of the configuration.

Novel electrochemical route to 2-(α-alkoxyallyl)phenols - Cathodic eliminative ring opening reaction

Electrochemical reduction of 4-alkoxy-3-bromochromans in acetonitrile led to a facile ring cleavage reaction yielding (2(α-alkoxy- allyl)phenols which are not easily accessible.

A New Route to o-Allenylphenols

Cathodic reduction of 3-bromochromenes led to a ring-opening reaction yielding o-allenylphenyl acetates.

o-Benzoquinone Methide: An Intermediate in the Gas-Phase Pyrolysis of Chroman

Gas-phase pyrolysis of chroman gives o-cresol, benzofuran, and styrene in a 4:2:1 ratio at 413 deg C.In the presence of 2-butene, a moderately stereospecific 4 + 2 reaction occurs with the likely intermediate, o-benzoquinone methide, 1.The addition of 2-butene increased the amount of reaction and decreased the extent of formation of benzofuran and styrene.Addition of hydrogen gas increased the amount of hydrodealkoxylation product, styrene, and gave more of its reduction product, ethylbenzene, at the expense of benzofuran.Only a slight increase in the amount of o-cresol was observed upon addition of hydrogen gas.No dehydrochroman was observed in the reactions, and pyrolysis of 4H- and 2H-benzopyran gave no o-cresol, but instead gave styrene, benzofuran, 1-indanone, and some chroman.

Anti-juvenile hormones

Potential insect control compounds which are chromenes, as well as their method of preparation and use, are disclosed. Compounds have been found which are effective in the control of insects by inhibiting the actions of juvenile hormone. Examples of useful compounds are 6,7-dimethoxy-2,2-dimethyl-3-chromene and 7-methoxy-2,2-dimethyl-3-chromene which can be extracted from the common bedding plant Ageratum houstonianum. Such compounds act to induce precocious maturation of immature insects, resulting in death either during or within a short time before or after the molting process. Additional effects which have been obtained include sterilization of mature insects, interruption of embryogenesis in insect eggs, the induction of diapause in insects and the prevention of sex pheromone secretion in insects.

Oxidation of Arylalkanols by S2O82--CuII

Products of oxidation of a series of arylalkanols by S2O82--CuII in acetic acid and acetonitrile are consistent with initial oxidation to aryl radical cations followed by either loss of a benzylic proton or C-C bond scission and subsequent oxidation of intermediate benzylic radicals by CuII to final products. 1-Arylalkanols (ArCHOHR)react by both paths, C-C bond scission increasing with stability of the radical R.. 2-Arylalkanols (ArCH2CHOHR) give chiefly C-C bond scission to benzyl radicals and RCHO.The 3- and 4-arylalkanols undergo chiefly proton loss, and the resulting radicals are oxidized with cyclization to chromans and 2-phenylfurans, respectively, both of which may by oxidized in turn to further products.

Anorexic chromans

Compounds within formula STR1 and their salts wherein X is alkylene of 2-4 carbon atoms; R1 is hydrogen or alkyl of 1-6 carbon atoms; R2 is hydrogen, alkyl of 1-6 carbon atoms or benzyl, or R1 and R2 together with the nitrogen atom to which they are attached form a 5-, 6- or 7-membered saturated ring; R3 is aryl; R4 is hydrogen or alkyl of 1-4 carbon atoms; and R5 is hydrogen or alkyl of 1-4 carbon atoms; have been found to possess mood-modifying and anorexia inducing activity.