4373-13-1

Basic information

• Product Name: 3,4-Dihydro-1-methylnaphthalene
• Synonyms: 1,2-Dihydro-4-methylnaphthalene;1-Methyl-3,4-dihydronaphthalene;3,4-Dihydro-1-methylnaphthalene
• CAS NO: 4373-13-1
• Molecular Formula: C₁₁H₁₂
• Molecular Weight: 144.21
• Mol File: 4373-13-1.mol
• Article Data: 2

Chemical Properties

• Boiling Point: 197.84°C (rough estimate)
• Appearance: /
• Density: 0.9895
• Refractive Index: 1.5758
• CAS DataBase Reference: 3,4-Dihydro-1-methylnaphthalene(CAS DataBase Reference)
• NIST Chemistry Reference: 3,4-Dihydro-1-methylnaphthalene(4373-13-1)
• EPA Substance Registry System: 3,4-Dihydro-1-methylnaphthalene(4373-13-1)

Safety Data

• Hazardous Substances Data: 4373-13-1(Hazardous Substances Data)

Usage

General Description

3,4-Dihydro-1-methylnaphthalene is a chemical compound that is commonly known as tetralin. It is a colorless liquid with a faint odor, and it is used as a solvent, a chemical intermediate, and a fuel additive. Tetralin is produced through the hydrogenation of naphthalene and is used in the production of dyes, as well as in the synthesis of certain pharmaceuticals and pesticides. It is also used as a carrier solvent in some consumer products, such as adhesives and coatings. Tetralin is considered to have low toxicity, but exposure to high levels may cause irritation to the eyes, skin, and respiratory system.

Upstream product

• 123078-57-9 2-cyclopropyl-2-phenylpropiophenone 
• 98213-30-0 1-methyl-1,2-dihydronaphthalene 

Downstream Products

• 140465-79-8 CTDP 31819 
• 10277-73-3 1-(2,3-dihydro-1H-inden-1-yl)ethan-1-one 
• 90-12-0 1-Methylnaphthalene 
• 58780-24-8 4-(4-methoxy-benzyl)-3-methyl-1,2,3,4,5,6-hexahydro-benzo[f]isoquinoline 
• 1444403-84-2 (E)-methyl 5-(2-acetylphenyl)pent-2-enoate 
• 1345876-83-6 (R,E)-methyl 2-((S)-4-methyl-1,2-dihydronaphthalen-2-yl)-4-phenylbut-3-enoate 
• 6279-88-5 1-methyl-3,4-dihydronaphthalene-2-carboxylic acid 
• 4024-14-0 1-methyl-2-tetralone 
• 771-13-1 1-methylnaphthalen-2-amine 

Relevant articles and documents

Photochemistry of 3-methyl- and 4-methyl-1,2-dihydronaphthalene in the gas phase1

The photochemistry of 3-methyl-1,2-dihydronaphthalene (3-MDHN) and 4-methyl-1,2-dihydronaphthalene (4-MDHN) has been studied in the gas phase. Photolysis of 3-MDHN with 254-nm light produces 2-methyl-1,2-dihydronaphthalene (2-MDHN) as the major primary product. Naphthalene is also formed, apparently as a secondary photoproduct from 2-MDHN. Addition of butane to the photolysis mixture quenches the formation of 2-MDHN while producing a new photoproduct, 1-isopropenylbenzocyclobutene (IBCB). This product is also formed when light centered at 300 nm is used for the photolysis. Photolysis of 4-MDHN vapor with 254-nm light gives three products unique to the gas phase: 1-isopropenyl-2-vinylbenzene (IVB), 3-(o-tolyl)-1,2-butadiene (T12B), and 1-methyl-1,2-dihydronaphthalene (1-MDHN). An apparent alkyl shift product, 3-methyl-1,2-dihydronaphthalene (3-MDHN), and naphthalene are also formed, apparently as secondary photolysis products from 1-MDHN. In addition, several photoproducts common to both the solution and gas phase are detected: 2-(o-tolyl)-1,3-butadiene (T13B), 1-methylbenzobicyclo[3.1.0]hex-2-ene (1-MBBH), 1-methyl-1,4-dihydronaphthalene (1-M-1,4-DHN), 1-methyltetralin (1-MT), and 1-methylnaphthalene (1-MN). Again, the presence of butane during the 254-nm photolysis, or the use of longer wavelength light, gives rise to a new photoproduct, 1-methyl-1-vinylbenzocyclobutene (MVBCB). The fluorescence excitation spectrum for 4-MDHN confirms that 254-nm excitation into S2 leads to minimal population of the emissive vibrational levels of S1. Two pathways appear to dominate the photochemistry: retro [4 + 2] cycloaddition to give o-quinodimethane intermediates and sequential hydrogen shifts. These pathways derive from S2 and/or upper vibrational levels of S1 (S1vib) as indicated by the characteristic responses of their ultimate products to the presence of buffer gas. The benzocyclobutenes are unique; they are postulated to arise through a 2 + 2 closure of a vibrationally relaxed precursor o-quinodimethane or via a [1,3] sigmatropic shift in a uniquely populated set of S1vib levels.