10504-06-0Relevant articles and documents
Production of p-Methylstyrene and p-Divinylbenzene from Furanic Compounds
Koehle, Maura,Sara?i, Erisa,Dauenhauer, Paul,Lobo, Raul F.
, p. 91 - 98 (2017)
A four-step catalytic process was developed to produce p-methylstyrene from methylfuran, a biomass-derived species. First, methylfuran was acylated over zeolite H-Beta with acetic anhydride. Second, the acetyl group was reduced to an ethyl group with hydrogen over copper chromite. Third, p-ethyltoluene was formed through Diels–Alder cycloaddition and dehydration of 2-ethyl-5-methyl-furan with ethylene over zeolite H-Beta. Dehydrogenation of p-ethyltoluene to yield p-methylstyrene completes the synthesis but was not investigated because it is a known process. The first two steps were accomplished in high yield (>88 %) and the Diels–Alder step resulted in a 67 % yield of p-ethyltoluene with a 99.5 % selectivity to the para isomer (final yield of 53.5 %). The methodology was also used for the preparation of p-divinylbenzene. It is shown that acylation of furans over H-Beta zeolites is a highly selective and high-yield reaction that could be used to produce other valuable molecules from biomass-derived furans.
Synthesis and crystallochromy of 1, 4, 7, 10-tetraalkyltetracenes: Tuning of solid-state optical properties of tetracenes by alkyl side-chain length
Kitamura, Chitoshi,Abe, Yasushi,Ohara, Takuya,Yoneda, Akio,Kawase, Takeshi,Kobayashi, Takashi,Naito, Hiroyoshi,Komatsu, Toshiki
, p. 890 - 898 (2010)
We synthesized a series of 1, 4, 7, 10-tetraalkyltetracenes using a new 2, 6-naphthodiyne precursor and 2, 5-dialkylfurans as starting materials (alkyl = methyl to hexyl). Surprisingly, the solid-state color of the tetracenes ranges through yellow, orange, and red. Both yellow and red solids are obtained for the butyl derivative. Optical properties in solution show no marked differences; however, those in the solid state show characteristics that vary with alkyl side-chain length: methyl, propyl, and pentyl derivatives are orange; ethyl and butyl derivatives are yellow; and another butyl and hexyl derivative are red. X-ray analyses reveal that the molecular structures are planar, semi-chair, or chair forms; the chair form takes a herringbone-like arrangement and the other forms take slipped parallel arrangements. The mechanism of crystallochromy is discussed in terms of molecular structure, crystal packing, and calculations that take account of exciton coupling.
Merging singlet-oxygen induced furan oxidations with organocatalysis: Synthesis of enantiopure cyclopentanones and hydrindanes
Kalaitzakis, Dimitris,Montagnon, Tamsyn,Sofiadis, Manolis,Tsopanakis, Vasileios,Vassilikogiannakis, Georgios
, p. 2817 - 2822 (2020)
A new methodology is described herein which converts simple and readily accesible furan substrates into complex enantio-enriched carbocyclic skeletons through the implementation of a simple one-pot procedure. Singlet oxygen furan photoxygenation affords an enedione which then participates in an organocatalysed double-Michael reaction with an enal to furnish a cyclopentanone structure with up to four new contiguous stereogenic centres. The enantioselectivity and diastereoselectivity of this process are both excellent. If desired, further aldol-annulation steps can be appended to the cascade reaction sequence to afford key enantiopure hydrindane motifs.
One-step synthesis method of 2, 5-dialkyl furan
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Paragraph 0021-0022, (2019/05/08)
Belonging to the field of organic synthesis, the invention relates to a one-step synthesis method of 2, 5-dialkyl furan. Specifically, the synthetic route is shown as the specification, wherein R is saturated chain hydrocarbon of 2-6 carbon atoms. The specific steps include: (1) adding furan, N, N'-tetramethylethylenediamine (TMEDA) and a solvent tetrahydrofuran (THF) into a reaction bottle, and performing stirring at a temperature ranging from -5DEG C to 0DEG C for 15-30min; (2) adding a 2-n-butyl lithium (n-BuLi) n-hexane solution dropwise, and then performing stirring at a temperature ranging from -5DEG C to 0DEG C for 15-30min; (3) heating the mixture to reflux; (4) transferring the mixture to room temperature for cooling, then transferring the mixture to ice-water bath (at a temperature ranging from -5DEG C to 0DEG C), and conducting stirring for 15-30min; and (5) adding brominated alkane dropwise, then performing heating to room temperature, and conducting stirring to the end ofreaction, and then performing post-treatment, thus obtaining 2, 5-dialkyl furan.
