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Upstream product

• 2717-44-4 2-methyl-3,4-dihydronaphthalene 
• 75074-58-7 4-phenyl-2-iodomethyl-1-butene 
• 75-09-2 dichloromethane 
• 530-93-8 1,2,3,4-tetrahydronaphthalen-2-one 
• 75-05-8 acetonitrile 

Relevant academic research and scientific papers

Dichloromethane activation. Direct methylenation of ketones and aldehydes with CH2Cl2 promoted by Mg/TiCl4/THF

(Chemical Equation Presented) This Mg-TiCl4-promoted CH 2-transfer reaction of CH2Cl2 represents an extremely simple, practical, and efficient methylenation of a variety of ketones and aldehydes, especially in enolizable or sterically hindered ketones such as 2,2-dimethylcyclohexanone, camphor, and fenchone.

Photochemistry of 3-methyl- and 4-methyl-1,2-dihydronaphthalene in solution

Photolysis of 3-methyl-1,2-dihydronaphthalene (3-MDHN) in hexane solution with 254-nm light produces one major product, 5-methylbenzobicyclo[3.1.0]hex-2-ene(5-MBBH; φ = 4.7 × 10-4). Photolysis in hexane in the presence of trifluoroacetic acid produces exclusively 2-methylene-1,2,3,4-tetrahydronaphthalene (2-MTHN). The 254-nm photolysis of 4-methyl-1,2-dihydronaphthalene (4-MDHN) in hexane produces 2-(o-tolyl)-1,3-butadiene (T13B; φ= 2.2 × 10-3), 1-methylbenzobicyclo[3.1.0]hex-2-ene (1-MBBH; φ= 1.4 × 10-3), 1 -methyl- 1,4-dihydronaphthalene (1-M-1,4-DHN; φ= 8.7 × 10-3), 1-methyltetralin (1-MT; φ= 1.5 × 10-3), and 1-methylnaphthalene (1-MN; φ= 2.7 × 10-3). Triplet sensitization of 4-MDHN produces only 1-MN in small amounts, suggesting that the direct photolyses proceed via singlet chemistry. The products appear to derive from a combination of electrocyclic opening of the cyclohexadienyl ring to generate an o-quinodimethane intermediate, disproportionation leading to net oxidation-reduction and, in 4-MDHN, a [1,3] hydrogen shift to form 1-M-1,4-DHN. The o-quinodimethane intermediates further react to form benzobicyclo[3.1.0]hex-2-ene derivatives (via a photochemical [4 + 2] cycloaddition; Scheme VI) and, in the case of 4-MDHN, the 1,3-butadiene T13B (via a thermal [1,5] hydrogen shift; Scheme VII).

The photochemical rearrangement of 1,2-dihydronaphthalenes into 1,4-dihydronaphthalenes induced by amines

The synthetic usefulness of the deprotonation/protonation reaction of excited 1,2-dihydronaphthalenes into 1,4-dihydronaphthalenes induced by amines has been investigated using 13 different substituted 1,2-dihydronaphthalenes and related compounds.The yield of the rearrangement ranges from 5 to 96percent.The formation of side-products depends on the position of protons in the substrate, which can be abstracted by the amine, and on competitive photoreactions.

Photochemistry of 3-methyl-1,2-dihydronaphthalene

Irradiation of the title compound (6) with a broad spectrum lamp at room temperature afforded 2-methylidene-1,2,3,4-tetrahydronaphthalene(8) and 2-methylnaphthalene (7).Apart from 8, irradiation of 6 at -45 deg also afforded 5-methylbenzobicyclohex-2-ene (12) 1-methylidene-2-(2-tolyl)cyclopropane (13) as well as a small amount of 2-methyl-1,4-dihydronaphthalene (14).Both 12 and 13 originate from the ring-opened product of 6.Compound 14 is probably formed via a retro di-?-methane rearrangement from 12.Irradiation of 6 in n-propylamine afford the same photoproducts, 14 being the main one in this case.

Acid-Catalyzed Photoisomerization of 2-Alkylindenes to 2-Alkylideneindanes

Photolysis of 2-alkylindenes in aprotic media containing hydrochloric acid leads to the formation of 2-alkylideneindanes with concomitant quenching of the previously reported phototransposition reaction.Quantum efficiencies range from 0.02 to 0.1 and, as with the tranposition reaction, are highest for those indenes having short singlet lifetimes.Though there is evidence that the reaction is derived from the singlet excited state, acid has no effect on fluorescence and therefore intervenes by protonating an intermediate formed from S1.This intermediate (proposed as the bicyclopentene "I") is common to both the transposition and the olefin migration (cf.Scheme III).

The photochemistry of 4-phenyl-1-iodobutane and 4-phenyl-2-iodomethyl-1-butene

The photochemistry of 4-phenyl-1-iodobutane 3 and 4-phenyl-2-iodomethyl-1-butene 4 has been studied to investigate the effect of structure on the character of the intermediates generated on photolysis.The irradiation of the simple primary iodide 3 appears to yield only radical intermediates.By contrast the photolysis of the allylic iodide 4 yields products that are more consistent with cationic intermediates.