4167-75-3Relevant academic research and scientific papers
Non-catalytic anti-Markovnikov phenol alkylation with supercritical water
Sato, Takafumi,Ishiyama, Yasuyoshi,Itoh, Naotsugu
, p. 716 - 717 (2006)
The anti-Markovnikov alkylation of phenol with tert-butyl alcohol could be achieved without catalyst in supercritical water at 673 K. The dehydration of tert-butyl alcohol gave isobutene and was followed by the reaction with phenol to form 2-isobutylphenol as an anti-Markovnikov product, 2-tert-butylphenol and 4-tert-butylphenol. The hydroxy group probably participated in the anti-Markovnikov alkylation and the increase in water density enhanced the formation of 2-isobutylphenol as well as 4-tert-butylphenol. Copyright
Improved Synthesis of MediPhos Ligands and Their Use in the Pd-Catalyzed Enantioselective N-Allylation of Glycine Esters
Albat, Dominik,Neud?rfl, J?rg-Martin,Reiher, Martin,Schmalz, Hans-Günther
supporting information, p. 4237 - 4242 (2021/08/24)
A new class of chiral C2-symmetric diphosphines (MediPhos) was recently shown to give superior results in the Pd-catalyzed asymmetric N-allylation of amino acid esters. We here describe a new, improved protocol for the preparation of such ligands through bidirectional SN2-coupling of a tartrate-derived ditosylate with 6-alkyl-2-bromophenols followed by double lithiation/phosphanylation. This method gave access to a series of nine ligands with branched alkyl substituents, which were benchmarked in the enantioselective Pd-catalyzed N-allylation of tert-butyl glycinate with racemic (E)-2,8-dimethylnona-5-en-4-yl methyl carbonate (up to 95 % ee). In addition, the analogous transformation of tert-butyl glycinate with methyl (E)-nona-5-en-4-yl carbonate was optimized. The obtained allylic amines were then used in the stereoselective synthesis of the conformationally restricted proline-derived dipeptide analogs ProM-17 and ProM-21.
Thermal Stability Study of 4-tert-Butylphenol
Shakun,Nesterova,Naumkin
, p. 120 - 127 (2019/04/27)
Abstract: The thermal stability of 4-tert-butylphenol has been studied in the temperature range of 673–738?K, the components of the thermolysis reaction mixture have been identified, a kinetic model of the process has been proposed, and the rate constants and parameters of the Arrhenius equation have been calculated for all of the reactions considered. The predominant role of 4-tert-butylphenol isomerization transformations has been established. Information on the 4-tert-butylphenol thermal stability facilitates to a more substantiated approach to its use as an additive that increases the oxidative stability of fuels and lubricants, as well as an antioxidant for polymer compositions.
Improved and scalable synthesis of building blocks for the modular synthesis of teraryl-based alpha-helix mimetics
Trobe, Melanie,Breinbauer, Rolf
, p. 509 - 521 (2016/03/19)
The modular synthesis of teraryl-based alpha-helix mimetics can be accomplished by sequential Suzuki-couplings of arylboronic acid building blocks with 4-iodophenyltriflate core-fragments. We report about new synthetic accesses to core fragments featuring
A modular synthesis of teraryl-based α-helix mimetics, part 1: Synthesis of core fragments with two electronically differentiated leaving groups
Peters, Martin,Trobe, Melanie,Tan, Hao,Kleineweischede, Rolf,Breinbauer, Rolf
supporting information, p. 2442 - 2449 (2013/04/24)
Teraryl-based α-helix mimetics have proven to be useful compounds for the inhibition of protein-protein interactions (PPI). We have developed a modular and flexible approach for the synthesis of teraryl-based α-helix mimetics. Central to our strategy is the use of a benzene core unit featuring two leaving groups of differentiated reactivity in the Pd-catalyzed cross-coupling used for terphenyl assembly. With the halogen/diazonium route and the halogen/triflate route, two strategies have successfully been established. The synthesis of core building blocks with aliphatic (Ala, Val, Leu, Ile), aromatic (Phe), polar (Cys, Lys), hydrophilic (Ser, Gln), and acidic (Glu) amino acid side chains are reported. Turn on: Teraryl-based α-helix mimetics can be effectively produced by sequential Suzuki coupling of a central core fragment featuring electronically differentiated leaving groups with aryl boronic pinacol esters (see scheme; dppf=1,1′-bis(diphenylphosphino) ferrocene, DME=dimethoxyethane, Pin=pinacol, Tf=trifluoromethanesulfonyl). With a set of only 2×18 building blocks, all permutations of α-helix mimetics can be produced. Copyright
Reductive lithiation of alkoxy-substituted benzyl methyl ethers and connection with cross-coupling reactions
Azzena, Ugo,Dettori, Giovanna,Pireddu, Roberta,Pisano, Luisa
, p. 1617 - 1623 (2007/10/03)
2-and 4-Ethoxymethoxybenzyl methyl ethers were employied as useful starting materials for the synthesis of 1,2- or 1,4-dicarbo-substituted benzenes. The proposed reaction sequence involves connection between the reductive lithiation of benzyl alkyl ethers and the metal-catalyzed cross-coupling reaction of aromatic triflates.
Crystalline MWW-type titanosilicate catalyst for producing oxidized compound, production process for the catalyst, and process for producing oxidized compound by using the catalyst
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, (2008/06/13)
A crystalline titanosilicate catalyst which is usable as a catalyst in the oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group, a process for producing the catalyst, and a process for producing an oxidized compound by an oxidation reaction using the catalyst. It has been found that a crystalline titanosilicate having a structural code of MWW effectively functions as a catalyst in an oxidation reaction of a compound having a carbon-carbon double bond and at least one other functional group, or a compound having a carbon-carbon double bond a functional group and having a total carbon number of not smaller than 2 and not larger than 5, wherein the carbon-carbon double bond of the compound is oxidized by using a peroxide as an oxidizing agent, thereby to highly selectively provide an intended oxidized compound.
Derivatives of pyrimido[6,1-a]isoquinolin-4-one
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, (2008/06/13)
The invention provides compounds or salts thereof of the general formula (I): wherein each of R1and R2 independently represents a C1-6 alkyl or C2-7 acyl group; X represents OCH2 or a group CR3R4; wherein each of R3 or R4 independently represents a hydrogen atom or a C1-3 alkyl group; R5 represents a hydrogen atom or a C1-3 alkyl, C2-3 alkenyl or C2-3 alkynyl group; R6 represents a hydrogen atom or a C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, amino, C1-6 alkylamino, di(C1-6) alkylamino or C2-7 acylamino group; each of R7 and R8 independently represents a hydrogen or halogen atom or a hydroxy, trifluoromethyl, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C2-7 acyl, C1-6 alkylthio, C1-6 alkoxy, C3-6 cycloalkyl; and R9 represents a hydrogen or halogen atom or a hydroxy, trifluoromethyl, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C2-7 acyl, C1-6 alkylthio, C1-6 alkoxy or C3-6 cycloalkyl group. The compounds or salts thereof are useful for treatment of respiratory disorders such as asthma. Compounds of the invention have a longer duration of action than the known compound trequinsin (9,10-dimethoxy-3 methyl-2-mesitylimino-2,3,6,7-tetrahydro-4H-pyrimido[6,1-a]isoquinolin-4-one).
Hydroformylation of acyclic monoethylenically unsaturated compounds to corresponding terminal aldehydes
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, (2008/06/13)
A process for hydroformylatiog acyclic monoethylenically unsaturated compounds to corresponding terminal aldehydes using a Group VIII transition metal and selected multidentate phosphite ligands.
