575-37-1

Usage

Uses

Used in Fragrance Industry:
1,7-Dimethylnaphthalene is used as a fragrance ingredient for its distinct aromatic properties. It contributes to the unique scent of essential oils derived from plants like Phyllostachys violascens, Sinobambusa tootsik, Sasa subglabra, and Pleioblastus kongosanensis.
Used in Antioxidant Applications:
1,7-Dimethylnaphthalene is used as an antioxidant in various industries, including the pharmaceutical and cosmetic sectors, due to its differential antioxidant activity. This property helps protect products from oxidative damage, extending their shelf life and maintaining their quality.
Used in Chemical Research:
1,7-Dimethylnaphthalene serves as a valuable compound in chemical research and development, particularly in the synthesis of various organic compounds and materials. Its unique structure and properties make it a useful building block for creating new molecules with specific applications in different fields.

InChI:InChI=1/C12H12/c1-9-6-7-11-5-3-4-10(2)12(11)8-9/h3-8H,1-2H3

Upstream product

• 66295-01-0 4,6-dimethyl-1,2-dihydro-naphthalene 
• 87662-78-0 3,5-Dimethyl-naphthalen-1-ylamine 
• 67-56-1 methanol 
• 91-57-6 2-Methylnaphthalene 
• 858022-38-5 4,6-dimethyl-[2]naphthoic acid 
• 4619-20-9 3-(4-methylbenzoyl)propionic acid 
• 573-98-8 dimethyl-1,2 naphtalene 
• 569-41-5 1,8-dimethylnaphthalene 
• 91-20-3 naphthalene 
• 25419-35-6 1,7-dimethyl-1,2,3,4-tetrahydronaphthalene 
• 802294-64-0 propionic acid 
• 201230-82-2 carbon monoxide 
• 581-40-8 2,3-dimethylnaphthalene 
• 571-58-4 1,4-dimethylnaphthalene 

Downstream Products

• 23802-62-2 trans-1,7-Distyryl-naphthalin 
• 582-16-1 2,7-dimethylnaphthalene 
• 2497-54-3 2,10-Dimethylphenanthrene 
• 2131-42-2 1,4,6-trimethylnaphthalene 

Relevant academic research and scientific papers

Synthesis and spectroscopic properties of 4a,14a-diazoniaanthra[1,2-a] anthracene and 13a,16a-diazoniahexaphene derived from 1,7-dimethylnaphthalene

An improved preparation of 1,7-dimethylnaphthalene is presented, which is used as a precursor for the synthesis of diazoniahexacyclic salts, namely, 4a,14a-diazoniaanthra[1,2-a]anthracene (3) and 13a,16a-diazoniahexaphene (7). The influence of the reaction conditions on the formation of these isomers was investigated. Notably, the selectivity of the reactions depends significantly on the acid employed in the cyclization step. Both compounds exhibit similar absorption and fluorescence emission properties. Compound 3 exhibits a remarkable photopersistence in the solid state and in air-saturated aqueous solutions. However, diazoniahexaphene 7 undergoes rapid photodegradation in solution. X-ray diffraction analysis reveals that compound 3 adopts a helicene structure in the crystalline state. Georg Thieme Verlag Stuttgart.

Synthesis of Nanosized ZSM-5 Zeolites by Different Methods and Their Catalytic Performance in the Alkylation of Naphthalene

Abstract: Three nanosized ZSM-5 zeolites were successfully prepared from reactive gelswith the same Si/Al ratios by different synthetic procedures that included theuse of tetrapropylammonium hydroxide or n-butylamine as a template and a seedingmethod that did not use an organic additive. The effect of the synthetic methodon the physicochemical properties of the prepared samples was investigated byXRD, XRF, XPS, N2 physisorption, SEM, TEM,27Al MAS NMR, NH3-TPD, andPy-FTIR. The catalytic performance of thenanosized ZSM-5 zeolites in the alkylation of naphthalene with methanol wascompared. The prepared samples were phase-pure, highly crystalline ZSM-5zeolites, but they had different bulk and surface Si/Al ratios as well astextural and acidic properties. The study of the prepared catalysts innaphthalene methylation revealed that both the acid characteristics of the ZSM-5nanosized zeolites and their textural properties were responsible for theiractivity in the reaction. A difference in the composition ofmonomethylnaphthalenes and dimethylnaphthalenes was attributed to the ability ofthe catalyst to isomerize the primary reaction products on acid sites located onthe external surface of the zeolite crystals. 2,7-DMN was found to be thepreferred reaction product over 2,6-DMN when formed at pore entrances to ZSM-5channels due to the differences in their dimensions. In contrast,2,6-dimethylnaphthalene could be produced on weaker external Br?nsted acidsites, which are hydroxyls attached to octahedral Al atoms. The presentedresults show that the method used to synthesize nanoscale ZSM-5 zeolites is acritical factor that determines the physicochemical properties and catalyticperformance of the resulting crystals.

Methylation of 2-methylnaphthalene over metal-impregnated mesoporous MCM-41 for the synthesis of 2,6-triad dimethylnaphthalene isomers

2,6-Dimethylnaphthalene (2,6-DMN) is one of the key intermediates for the production of polyethylene naphthalate (PEN), which demonstrates superior properties compared with the polyethylene terephthalate. However, the complex synthesis procedure of 2,6-DMN increases the production cost and decreases the commercialisation of PEN. In this study, selective synthesis of 2,6-triad DMN isomers (1,5-DMN, 1,6-DMN and 2,6-DMN) has been investigated by the methylation of 2-methylnaphthalene (2-MN) over mesoporous Cu/MCM-41 and Zr/MCM-41 zeolite catalysts. On the contrary of other DMN isomers, 2.6-triad isomers can effectively be converted to be profitable 2,6-DMN with an additional isomerisation reaction, which is a new approach to reach higher 2,6-DMN yield. The methylation reactions of 2-MN were investigated in a fixed-bed reactor at 400?°C and weight hourly space velocity of 1–3?h?1. The results showed that the activity of MCM-41 on the methylation of 2-MN has been enhanced with the impregnation of Cu. The conversion increased from about 17% to 35 wt% with the impregnation of Cu. Similarly, the 2,6-triad DMN selectivity and 2,6-/2,7-DMN ratio reached the maximum level (48 wt% and 1.95, respectively) over Cu-impregnated MCM-41 zeolite catalyst.

Selective synthesis of 2,6-triad dimethylnaphthalene isomers by disproportionation of 2-methylnaphthalene over mesoporous MCM-41

2,6-Dimethylnaphthalene (2,6-DMN) is one of the crucial intermediates for the synthesis of polybutylenenaphthalate and polyethylene naphthalate (PEN). The complex synthesis procedure and the high cost of 2,6-DMN production significantly reduce the commercialisation of PEN even though PEN demonstrates superior properties compared with polyethylene terephthalate. 2,6-DMN can be produced by methylation of 2-methylnaphthalene (2-MN) and/or naphthalene, disproportionation of 2-MN, and/or isomerisation of dimethylnaphthalenes (DMNs). In this study, synthesis of 2,6-triad DMN isomers consisting of 2,6-DMN, 1,6-DMN, and 1,5-DMN have been investigated with the disproportionation of 2-MN over unmodified and Zr-modified mesoporous MCM-41 zeolite catalysts. In contrast to other DMN isomers, both 1,5-DMN and 1,6-DMN can be effectively isomerised to be profitable 2,6-DMN. The disproportionation of 2-MN experiments were carried out in a catalytic fixed-bed reactor in the presence of 1?g of catalyst at a temperature range of 350–500?°C and weight hourly space velocity between 1 to 3?h?1. The results demonstrated that mesoporous MCM-41 zeolite catalyst has a selective pore shape for 2,6-triad DMN isomers, which may allow a decrease in the production cost of 2,6-DMN. Additionally, 2,6-DMN was successfully synthesised by the disproportionation of 2-MN over MCM-41 zeolite catalyst. Furthermore, both the conversion of 2-MN and the selectivity of 2,6-DMN were considerably enhanced by the Zr impregnation on MCM-41.

Conversion of propionic acid and 3-pentanone to hydrocarbons on ZSM-5 catalysts: Reaction pathway and active site

Conversion of propionic acid to gasoline-range molecules was investigated at 350?°C on a series of ZSM-5 catalysts with varying density of Br?nsted acid sites (BAS), achieved by ion exchange of proton with Na+. Ketonization of propionic acid to 3-pentanone is the primary reaction, with the sequential aldol condensation to dipentanone alcohol being the secondary. The major reaction pathway for forming the aromatics involves dehydration, cyclization, dehydration and hydride transfer from dipentanone alcohol, leading to the formation of C10 aromatics before being dealkylated to lighter aromatics. Temperature programmed desorption of propionic acid indicates that the reaction initiates with acylium cation formation on BAS through dehydration. Comparing the turnover frequencies of ketonization and aldol condensation on ZSM-5 with varying density of BAS indicates that BAS is the active site for both reactions. The propionic acid feed deactivates the catalyst faster than the 3-pentantone feed due to a stronger adsorption of propionic acid on the acid sites of ZSM-5.

K-promoted Mo/Co- and Mo/Ni-catalyzed Fischer-Tropsch synthesis of aromatic hydrocarbons with and without a Cu water gas shift catalyst

The catalyst systems Mo/Co/K/ZSM-5 and Mo/Ni/K/ZSM-5, alone and with the added copper-based water gas shift catalyst, were used for the conversion of two CO/H2 ratios in a batch reactor. GC analysis of the gas phase was used to determine CO conversion while GCMS and NMR studies were used to characterize the liquid products formed and liquid product selectivities. The liquids were hydrocarbons consisting mainly of alkyl substituted benzenes. Methyl substitution in the alkyl benzenes in the product liquid ranged from an average of 1.3 to 4.5 methyls per ring depending on reaction conditions and reactant gas mole ratios. The additional presence of the WGS catalyst significantly increased CO conversion in the reactions taking place at 280 °C from ～25% to ～90% while increasing selectivity toward higher average methyl substitution. Similar conversions and selectivities were observed with both a bio-syngas and a 50/50 mixture of H2 and CO.

Methylation of naphthalene on MTW-type zeolites. Influence of template origin and substitution of Al by Ga

Two templates, methyltriethylammonium bromide (MTEA) and tetraethylammonium bromide (TEA) were used to synthesize aluminosilicate ZSM-12 zeolites. Additionally, zeolites isomorphously substituted (partially or totally) by gallium were prepared with MTEA.

METHOD OF PURIFYING 2,7-DIMETHYLNAPHTHALENE

[PROBLEMS] To provide a process for industrially stably producing a highly purified 2,7-dimethylnaphthalene with high yield from a dimethylnaphthalene isomer mixture at low production cost through convenient means. [MEANS FOR SOLVING PROBLEMS] There is provided a method of purifying 2,7-dimethylnaphthalene, characterized by including the step of bringing a raw oil containing a mixture of 1,7-dimethylnaphthalene and 2,7-dimethylnaphthalene together with a developing solvent into contact with L-type zeolite to thereby effect adsorption of 1,7-dimethylnaphthalene.

New aromatic rearrangement accompanying ring closure of 2-arylpropylidenemalonodinitriles to 1-aminonaphthalene-2-carbonitriles

Cyclization and a rearrangement in concentrated sulfuric acid of 2-(4-substituted-phenyl)propylidenemalonodinitriles (1) into 1-amino-4-methyl-6-substituted-naphthalene-2-carbonitriles (5) appears to involve a series of steps such as ipso electrophilic attack of the protonated nitrile function on the para position of the phenyl group, opening of a spirobenzenium cation or its transformation, and ring reclosure to the naphthalene framework with participation of the secondary alkyl carbocation as an active electrophile.