82807-35-0Relevant academic research and scientific papers
Method for preparing olefin by catalyzing dehydration and deoxidation of polyhydroxy compound with organic molybdenum
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Paragraph 0109; 0111-0112; 0129; 0131-0132, (2020/07/02)
The invention discloses a method for preparing olefin by catalyzing dehydration and deoxidation of a polyhydroxy compound with organic molybdenum. The method comprises the following steps: reacting apolyhydroxy compound-containing raw material in the presence of an organic molybdenum-based catalyst to obtain olefin. According to the method, compounds containing nitrogen, sulfur, oxygen, phosphorus and other monodentate and polydentate coordination groups are used as organic ligands, and a series of organic molybdenum catalysts are prepared and used for catalyzing a deoxidation and dehydrationreaction of vicinal diol. The invention provides a cheap non-noble metal molybdenum-based catalyst, wherein the cost is greatly reduced.
Oxo-rhenium-catalyzed deoxydehydration of polyols with hydroaromatic reductants
Boucher-Jacobs, Camille,Nicholas, Kenneth M.
supporting information, p. 1985 - 1990 (2015/06/08)
Several dihydroaromatic compounds are shown to be effective reducing agents in the oxo-metal-catalyzed deoxydehydration of diols and polyols to produce olefins and the corresponding arenes. NH4ReO4 and MeReO3 are active catalysts for the reactions. The most effective of the hydroaromatic reductants is indoline, which is oxidized to indole. Yields for a variety of diols and polyols range from 35% to 99%. Two hydrogen donors, 1,3-cyclohexadiene and dihydroanthracene, engage in tandem DODH/cycloaddition reactions. Competition experiments show that indoline is more reactive than representative alcohols in H-transfer. Indoline is shown to reduce MeReO3 to MeReO2 via an isolable adduct, MeReO3(indoline) (4), which has been structurally characterized and is suggested to be an intermediate in the catalytic DODH process.
In situ generation technology of β-butoxycarbonyliodonium ylide: A hypervalent analogue of the Darzens reagent
Miyamoto, Kazunori,Suzuki, Mai,Suefuji, Takashi,Ochiai, Masahito
supporting information, p. 3662 - 3666 (2013/07/19)
An ester exchange reaction of β-butoxy-β-acyloxyvinyl- λ3-iodane with lithium bases (ROLi and nBuLi) efficiently generates highly labile monoester iodonium ylide at low temperature. The iodonium ylide generated in situ cleanly undergoes Darzens condensation with aromatic aldehydes to afford trans-epoxy ester selectively. The reactivity of monoester iodonium ylide is investigated. Highly labile mono ester iodonium ylide generated in situ from β-butoxy-β-acyloxyvinyl- λ3-iodane through an ester exchange reaction cleanly undergoes Darzens-type condensation with aromatic aldehydes to afford trans-epoxy ester selectively. Copyright
Terpenic compounds as renewable sources of raw materials for cross-metathesis
Borre, Etienne,Dinh, Trong Hoa,Caijo, Frederic,Crevisy, Christophe,Mauduit, Marc
scheme or table, p. 2125 - 2130 (2011/08/03)
Dihydromyrcenol is used as a hydrated masked form of citronellene in olefin cross-metathesis reactions in order to solve the selectivity problem that results from the presence of two double bonds in many terpenes. Several ruthenium catalysts are evaluated, with the best, M71-SIPr, utilized in the cross-metathesis of dihydromyrcenol with various olefins affording the expected products in good yields. It is shown that the masked double bond can be regenerated via an acid-catalyzed elimination reaction and the product is then subjected to a further cross-metathesis reaction with a second olefin. Georg Thieme Verlag Stuttgart ? New York.
Homobimetallic ruthenium-N-heterocyclic carbene complexes: Synthesis, characterization, and catalytic applications
Sauvage, Xavier,Borguet, Yannick,Noels, Alfred F.,Delaude, Lionel,Demonceau, Albert
, p. 255 - 265 (2008/02/03)
Two new homobimetallic ruthenium-arene complexes [(p-cymene)Ru(μ-Cl) 3RuCl(η2-C2H4)(L)], where L = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (3a) or 1,3-bis(2,4,6- trimethylphenyl)-4,5-dichloroimidazolin-2-ylidene (3b), were isolated in high yields upon heating a toluene solution of [RuCl2 (p-cymene)] 2 with 1 equivalent of carbene ligand under an ethylene atmosphere. They were characterized by NMR and TGA. Their catalytic activity was investigated in the atom transfer radical polymerization of vinyl monomers. In the polymerization of methyl methacrylate, complex 3a displayed faster reaction rates than 3b and the related phosphine-based complex 2a (L = tricyclohexylphosphine), although control was more effective with the latter catalyst. When n-butyl acrylate or styrene served as monomer, a major shift of reactivity was observed between complex 2a that promoted controlled radical polymerization, and complexes 3a or 3b that favored metathetical coupling. Further homocoupling experiments with various styrene derivatives confirmed the outstanding aptitude of complex 3a (and to a lesser extent of 3b) to catalyze olefin metathesis reactions. Contrary to monometallic ruthenium-arene complexes of the [RuCl2(p-cymene)(L)] type, the new homobimetallic species did not require the addition of a diazo compound or visible light illumination to initiate the ring-opening metathesis of norbornene or cyclooctene. When α,ω-dienes were exposed to 3a or 3b, a mixture of cycloisomerization and ring-closing metathesis products was obtained in a non-selective way. Addition of a terminal alkyne co-catalyst enhanced the metathetical activity while completely repressing the cycloisomerization process. Thus, quantitative conversions of diethyl 2,2-diallylmalonate and N,N-diallyltosylamide were achieved within 2 h at room temperature using 2 mol% of catalyst precursor 3 a and 6 mol % of phenylacetylene.
