5205-07-2Relevant articles and documents
Preparation method of 1-halogenated-2-methyl-4-substituted carbonyloxy-2-butene
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Paragraph 0053-0054, (2020/08/18)
The invention provides a preparation method of 1-halogenated-2-methyl-4-substituted carbonyloxy-2-butene. According to the method, 2-methyl-4-hydroxy-1-butene and an acylation reagent are subjected toan acylation reaction under the action of a catalyst to prepare 2-methyl-4-substituted carbonyloxy-1-butene, and then the 2-methyl-4-substituted carbonyloxy-1-butene and halogen are subjected to an addition reaction and an alkali elimination reaction to prepare 1-halogenated-2-methyl-4-substituted carbonyloxy-2-butene. The method has the advantages of cheap and accessible raw materials and low product cost; the process flow is simple and convenient, the reaction conditions are easy to realize, the operation is safe, simple and convenient, the wastewater yield is low, and the method is green and environment-friendly; and the method also has the advantages of stable reaction intermediate product, proper reaction activity, high reaction selectivity, few side reactions and high target productyield and purity, and is suitable for green industrial production.
Iron-Nickel Dual-Catalysis: A New Engine for Olefin Functionalization and the Formation of Quaternary Centers
Green, Samantha A.,Vásquez-Céspedes, Suhelen,Shenvi, Ryan A.
supporting information, p. 11317 - 11324 (2018/09/18)
Alkene hydroarylation forms carbon-carbon bonds between two foundational building blocks of organic chemistry: olefins and aromatic rings. In the absence of electronic bias or directing groups, only the Friedel-Crafts reaction allows arenes to engage alkenes with Markovnikov selectivity to generate quaternary carbons. However, the intermediacy of carbocations precludes the use of electron-deficient arenes, including Lewis basic heterocycles. Here we report a highly Markovnikov-selective, dual-catalytic olefin hydroarylation that tolerates arenes and heteroarenes of any electronic character. Hydrogen atom transfer controls the formation of branched products and arene halogenation specifies attachment points on the aromatic ring. Mono-, di-, tri-, and tetra-substituted alkenes yield Markovnikov products including quaternary carbons within nonstrained rings.
Expedient Access to 2,3-Dihydropyridines from Unsaturated Oximes by Rh(III)-Catalyzed C-H Activation
Romanov-Michailidis, Fedor,Sedillo, Kassandra F.,Neely, Jamie M.,Rovis, Tomislav
supporting information, p. 8892 - 8895 (2015/08/03)
α,β-Unsaturated oxime pivalates are proposed to undergo reversible C(sp2)-H insertion with cationic Rh(III) complexes to furnish five-membered metallacycles. In the presence of 1,1-disubstituted olefins, these species participate in irreversible migratory insertion to give, after reductive elimination, 2,3-dihydropyridine products in good yields. Catalytic hydrogenation can then be used to convert these molecules into piperidines, which are important structural components of numerous pharmaceuticals.
Mg(ClO4)2 as a powerful catalyst for the acylation of alcohols under solvent-free conditions
Bartoli, Giuseppe,Bosco, Marcella,Dalpozzo, Renato,Marcantoni, Enrico,Massaccesi, Massimo,Rinaldi, Samuele,Sambri, Letizia
, p. 39 - 42 (2007/10/03)
A trace amount of magnesium perchlorate (from 0.1 mol% to 1 mol%) is able to promote quantitative acylation, with anhydrides, of a large variety of functionalized alcohols in short times, at room temperature and under solvent-free conditions.
Syntheses of novel 4-tert-alkyl ether proline-based 16- and 17-membered macrocyclic compounds
Chen, Kevin X.,Njoroge, F. George,Vibulbhan, Bancha,Buevich, Alexei,Chan, Tze-Ming,Girijavallabhan, Viyyoor
, p. 2730 - 2733 (2007/10/03)
Starting from N-Cbz-4-hydroxyproline methyl ester 1, a boron trifluoride-diethyl etherate-catalyzed reaction provided 4-tert-alkyl ether proline 4. Two deprotections and amide bond formations furnished the phenol alcohol 2. The macrocyclization of 2 was accomplished through a Mitsunobu reaction using triphenylphosphine and 1,1′-(azodicarbonyl)dipiperidine (ADDP), to afford novel 16- and 17-membered proline-based macrocyclic compounds of type 3.
Isoprene related esters, significant components of Pandanus tectorius
Vahirua-Lechat,Menut,Roig,Bessiere,Lamaty
, p. 1277 - 1279 (2007/10/03)
Isopentenyl and dimethylallyl acetates and cinnamates have been found in large amounts in an essential oil obtained from the ripe fruit of Pandanus tectorius, their identification has been confirmed by synthesis. This is the first time that these esters, apart from one, have been found in the plant kingdom and, generally speaking, that monoterpene precursors predominate in an essential oil.
SYNTHESIS WITH MANGANIC SALTS; PART III: SYNTHESIS OF 1,4-DIKETONES THROUGH MANGANIC ACETATE-MEDIATED ADDITION OF KETONE TO ISOPENTENYL SULFONES. ACETOXYLATION OF Β,Γ-UNSATURATED KETONES BY MANGANOUS AND CUPRIC ACETATES
Breuilles, Pascal,Uguen, Daniel
, p. 705 - 720 (2007/10/02)
Conditions have been found to selectively add ketones to isopentenyl sulfones.The major product, a ketone bearing a methylene group at the γ position, gave upon ozonolysis the corresponding 1,4-diketone.The usefulness of the overall process was illustrated by the efficient syntheses of jasmone and of one half of pyrenophorine.The γ-acetoxy conjugated enones that invariably formed during these additions resulted from the oxidation of an isomeric β,γ-unsaturated ketone by manganous and cupric acetates.Such an acetoxylation has been used to prepare 6β-acetoxy-cholestenone from cholesterol and also to prepare chrysanthemic acid.
117. Short Synthesies of (+/-)-Grandisol and (+/-)-Lineatin via a Common Intermediate
Aljancic-Solaja, Ivana,Rey, Max,Dreiding, Andre S.
, p. 1302 - 1306 (2007/10/02)
A 6-step synthesis of (+/-)-grandisol (1) is presented, which involves dichloroketene addition to 3-methyl-3-butenyl acetate (4), reductive dechlorination of the adduct 6 to the ketone 7 and saponification to 8, aldolization of 7 or 8 with acetone and cyclization to the bicyclic ketone 9, Wolff-Kishner reduction to 14, and finally ring opening to 1.Since 9 is a known intermediate of the synthesis of (+/-)-lineatin (2), the latter can now be obtained in 6 steps.
BASIC ELIMINATION OF SULFONIUM SALTS. NEIGHBOURING GROUP INFLUENCE ON REGIOSELECTIVITY.
Badet, B.,Julia, M.,Mallet, J. M.,Schmitz, C.
, p. 4331 - 4334 (2007/10/02)
A simple preparation of sulfonium salts functionalized by oxygenated groups is reported.The nature and the position of the latter control the regiochemistry of elimination of the sulfonium moiety leading to selective formation of Saytsev or Hofmann olefins.
