20213-26-7

Basic information

• Product Name: 6-METHOXY-2,2-DIMETHYL-3,4-DIHYDRO-2H-BENZO[H]CHROMENE
• Synonyms: 6-METHOXY-2,2-DIMETHYL-3,4-DIHYDRO-2H-BENZO[H]CHROMENE
• CAS NO: 20213-26-7
• Molecular Formula: C₁₆H₁₈O₂
• Molecular Weight: 242.31292
• Mol File: 20213-26-7.mol
• Article Data: 7

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 6-METHOXY-2,2-DIMETHYL-3,4-DIHYDRO-2H-BENZO[H]CHROMENE(CAS DataBase Reference)
• NIST Chemistry Reference: 6-METHOXY-2,2-DIMETHYL-3,4-DIHYDRO-2H-BENZO[H]CHROMENE(20213-26-7)
• EPA Substance Registry System: 6-METHOXY-2,2-DIMETHYL-3,4-DIHYDRO-2H-BENZO[H]CHROMENE(20213-26-7)

Safety Data

• Hazardous Substances Data: 20213-26-7(Hazardous Substances Data)

Upstream product

• 84-85-5 4-methoxynaphth-1-ol 
• 870-63-3 prenyl bromide 
• 573-13-7 lapachenole 
• 101169-22-6 6-methoxy-2,2-dimethyl-2,3-dihydro-benzo[h]chromen-4-one 
• 107-86-8 3,3-dimethyl acrylaldehyde 
• 73584-59-5 1-(1-hydroxy-4-methoxynaphthalen-2-yl)ethanone 
• 556-82-1 3-methyl-2-buten-1-ol 

Downstream Products

• 4707-32-8 2,2-dimethyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione 
• 4707-33-9 α-lapachone 
• 573-13-7 lapachenole 

Relevant articles and documents

Two expedient syntheses of β-lapachone

Two short syntheses of β-llapachone (1) from readily available naphthols 2a,b and 3-methylbut-2-enal via a mild phenylboronic acid-mediated cyclization to 2H-chromenes 3a,b is reported.

Molecular iodine catalyst promoted synthesis of chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling

Molecular iodine as an inexpensive catalyst is described in the construction of 2-substituted or 2,2-disubstituted chromans and 4-aryl-3,4-dihydrobenzopyran-2-ones via [3+3] cyclocoupling. For the synthesis of chromans, phenols and allylic alcohols were refluxed in chloroform in presence of 20 mol % I2 while [3+3] cyclocoupling of phenols and cinnamic acids proceeded to give 4-aryl-3,4-dihydrobenzopyran-2-ones using 30 mol % I2. Later reaction occurs via a tandem hydroarylation- esterification process at 120-130°C under solvent free conditions. Chromans were obtained in 20-92% yields and substituted 4-aryl-3,4-dihydrobenzopyran-2- ones were obtained in 5-85% yields.

Concise synthesis of (±)-rhinacanthin A, dehydro α-lapachone, and β-lapachone, and pyranonaphthoquinone derivatives

A concise synthesis of (±)-rhinacanthin A is achieved in two steps by epoxidation of dehydro-α-lapachone, followed by chemo-and regioselective reduction. Dehydro-α-lapachone was also synthesized in two steps starting from 4-methoxy-1-naphthol by ethylenediamine diaetate (EDDA)-catalyzed benzopyran formation and a CAN-mediated oxidation reaction. β-Lapachone was synthesized in three steps from 4-methoxy-1-naphthol by benzopyran formation, catalytic hydrogenation, and Jones oxidation. As additional reactions, synthesis of pyranonaphthoquinone derivatives with the pyranokunthone B skeleton has been achieved in a single step from readily available 2-hydroxy-6-methoxy-1,4-naphthoquinone and 2-hydroxy-7-methoxy-1,4- naphthoquinone.

A novel method for the synthesis of substituted benzochromenes by ethylenediamine diacetate-catalyzed cyclizations of naphthalenols to α,β-unsaturated aldehydes. Concise synthesis of the natural products lapachenole, dihydrolapachenole, and mollugin

A new synthetic route for biologically interesting benzochromenes was developed starting from naphthalenols and α,β-unsaturated aldehydes in the presence of ethylenediamine diacetate. This methodology was applied for the total synthesis of the biologicall