132416-36-5Relevant articles and documents
A new design of organic radical batteries (ORBs): Carbon nanotube buckypaper electrode functionalized by electrografting
Aqil, Abdelhafid,Vlad, Alexandru,Piedboeuf, Marie-Laure,Aqil, Mohamed,Job, Nathalie,Melinte, Sorin,Detrembleur, Christophe,Jér?me, Christine
, p. 9301 - 9304 (2015)
A novel hybrid material displaying a fast and reversible charge storage capability is prepared by electrografting of an alkoxyamine-bearing acrylate onto a carbon nanotube buckypaper, followed by the quantitative generation of an electroactive polynitroxi
The thermal reaction of sterically hindered nitroxyl radicals with allylic and benzylic substrates: Experimental and computational evidence for divergent mechanisms
Babiarz, Joseph E.,Cunkle, Glen T.,DeBellis, Anthony D.,Eveland, David,Pastor, Stephen D.,Shum, Sai P.
, p. 6831 - 6834 (2002)
The reaction of stable sterically hindered nitroxyl radicals with benzylic and allylic substrates was investigated. An allyloxyamine derivative was obtained by the reaction of 2 molar equiv of a nitroxyl radical with an unactivated alkene. Experimental an
Radical crossover in nitroxide mediated 'living' free radical polymerizations
Hawker, Craig J.,Barclay, George G.,Dao, Julian
, p. 11467 - 11471 (1996)
The efficiency of exchange between the mediating nitroxide moieties at the termini of growing polymer chains during 'living' free radical polymerizations has been probed by a series of crossover experiments using functionalized unimolecular initiators. The design of appropriately substituted initiators permitted the synthesis of specifically functionalized model polymers which could be readily distinguished using high-performance liquid chromatography (HPLC). Using these models, the mixture of macromolecules obtained from a 1:1 combination of disparate initiators was separated and identified. The results reveal that exchange of the mediating nitroxide free radicals is a facile process and at essentially all stages of the polymerization a nearly statistical mixture of crossover products is obtained. The HPLC techniques developed are also useful in evaluating the extent of chain termination in nitroxide mediated 'living' free radical polymerizations.
LIQUID-CRYSTALLINE MEDIUM, METHOD FOR THE STABILISATION THEREOF, AND LIQUID-CRYSTAL DISPLAY
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Paragraph 0442-0446, (2021/05/04)
Liquid crystalline medium comprises (a) at least one substituted piperidine derivative (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds (Ia), and (b) at least one substituted cyclohexyl derivative (II). Liquid crystalline medium comprises (a) at least one substituted piperidine derivative of formula (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds of formula (Ia), and (b) at least one substituted cyclohexyl derivative of formula (II). n : 1-4; m : 4-n; Z1 : organic group having 4 binding sites; Z11, Z12 : -O-, -(C=O)-, -(N-R14)- or single bond, where Z11 and Z12 do not simultaneously represent -O-; r, s : 0 or 1; either Y11-Y14 : 1-4C alkyl; or Y11+Y12, Y13+Y14 : 3-6C divalent group; R11 : O-R13, oxygen free radical or OH, preferably O-R13, preferably isopropyloxy, cyclohexyloxy, acetophenyl-oxy or benzyloxy, or oxygen free radical (preferred); R12 : H, F, OR14, NR14R15, 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16) or (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16); R13 : 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), 1,4-cyclohexylene (in which at least one CH 2 group is optionally replaced by -O-, -CO- or -NR14-) or acetophenyl, isopropyl or 3-heptyl; R14, R15 : 1-10C alkyl, 1-10C acyl, aromatic 6-12C hydrocarbyl or 6-12C carboxylic acid; R16 : 1-10C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-); G : oxygen free radical; G1 : 1-4C alkyl; R21 : unsubstituted 2-7C alkenyl; A2 : cyclohexane-1,4-diyl, benzene-1,4-diyl, 2-fluorobenzene-1,4-diyl or 2,3-difluorobenzene-1,4-diyl; either p, q : 0-2; or p+q : 1-3; and R22 : 1-7C alkyl, 1-6C alkoxy or 2-6C alkenyloxy (all unsubstituted). Provided that when n is 1, R11 is oxygen free radical and -[Z11] r-[Z12] s is -O-, -(CO)-O-, -O-(CO)-, -O-(CO)-O-, -NR14- or -NR14-(CO)-, then [R12] m-Z1 is not 1-10C alkyl, cycloalkyl, cycloalkylalkyl or alkyl-cycloalkyl (in all groups at least one CH 2 group is optionally replaced by -O- such that two O atoms are not directly bonded with each other); and when n is 2 and R11 is O-R13, then R13 is not nitrogen-1-9C alkyl. Independent claims are also included for: (1) an electro-optical display or an electro-optical component comprising the above liquid crystalline medium; (2) preparing the liquid crystalline medium, comprising mixing (I) with (II), substituted 1-cyclohexyl-2,3-difluorobenzene derivatives of formula (IIIa), substituted 1-cyclohex-1-enyl-2,3-difluorobenzene derivatives of formula (IIIb), substituted 2,3-difluoro-biphenyl derivatives of formula (IIIc) or substituted 2',3'-difluoro-[1,1';4',1'']terphenyl compounds of formula (IIId) and/or substituted bicyclohexyl compounds of formula (IV); and (3) stabilizing the liquid crystalline medium, comprising adding a medium which comprises (I) and optionally 2,6-di-tert-butyl-4-(4-propyl-cyclohexyl)-phenol, 2,6-di-tert-butyl-4-(5-propyl-[1,3]dioxan-2-yl)-phenol, 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, 3,5-di-tert-butyl-4-hydroxy-benzoic acid 4-pentyl-cyclohexylmethyl ester, 2,5-bis-(1,1,3,3-tetramethyl-butyl)-benzene-1,4-diol and acrylic acid 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methyl-benzyl)-4-methyl-phenyl ester to a medium which comprises (II). R31 : unsubstituted 1-7C alkyl; R32 : 1-7C alkyl, 1-6C alkoxy or 2-6C alkenyloxy (all unsubstituted); m, n, o : 0 or 1; R41 : 1-7C alkyl or 2-7C alkenyl (both unsubstituted); and R42 : 1-7C alkyl, 1-6C alkoxy or 2-7C alkenyl (all unsubstituted).
LIQUID-CRYSTALLINE MEDIUM, METHOD FOR THE STABILISATION THEREOF, AND LIQUID-CRYSTAL DISPLAY
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Paragraph 0411; 0413-0415, (2021/05/04)
Liquid crystalline medium comprises (a) at least one substituted piperidine derivative (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds (Ia), and (b) at least one substituted 1-cyclohexylmethoxy-2,3-difluoro-benzene derivative (II). Liquid crystalline medium comprises (a) at least one substituted piperidine derivative of formula (I) excluding substituted carbonic acid dipiperidin-4-yl ester compounds of formula (Ia), and (b) at least one substituted 1-cyclohexylmethoxy-2,3-difluoro-benzene derivative of formula (II). n : 1-4; m : 4-n; Z1 : organic group having 4 binding sites; Z11, Z12 : -O-, -(C=O)-, -(N-R14)- or single bond, where Z11 and Z12 do not simultaneously represent -O-; r, s : 0 or 1; either Y11-Y14 : 1-4C alkyl; or Y11+Y12, Y13+Y14 : 3-6C divalent group; R11 : O-R13, oxygen free radical or OH, preferably O-R13, preferably isopropyloxy, cyclohexyloxy, acetophenyl-oxy or benzyloxy, or oxygen free radical (preferred); R12 : H, F, OR14, NR14R15, 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16) or (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16); R13 : 1-20C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where two adjacent CH 2 groups are not optionally replaced by -O-), hydrocarbyl, preferably cycloalkyl or alkyl-cycloalkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-, and 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), (hetero)aromatic hydrocarbyl (in which 1 H or several H are optionally replaced by OR14, N(R14)(R15) or R16), 1,4-cyclohexylene (in which at least one CH 2 group is optionally replaced by -O-, -CO- or -NR14-) or acetophenyl, isopropyl or 3-heptyl; R14, R15 : 1-10C alkyl, 1-10C acyl, aromatic 6-12C hydrocarbyl or 6-12C carboxylic acid; R16 : 1-10C alkyl (in which 1 CH 2 group or several CH 2 groups are optionally replaced by -O- or -C(=O)-, where 2 adjacent CH 2 groups are not optionally replaced by -O-); G : oxygen free radical; G1 : 1-4C alkyl; R41 : unsubstituted 1-7C alkenyl; R42 : 1-7C alkyl, 1-6C alkoxy or 2-6C alkenyloxy (all unsubstituted); and i : 0 or 1. Provided that when n is 1, R11 is oxygen free radical and -[Z11] r-[Z12] s is -O-, -(CO)-O-, -O-(CO)-, -O-(CO)-O-, -NR14- or -NR14-(CO)-, then [R12] m-Z1 is not 1-10C alkyl, cycloalkyl, cycloalkylalkyl or alkyl-cycloalkyl (in all groups at least one CH 2 group is optionally replaced by -O- such that two O atoms are not directly bonded with each other); and when n is 2 and R11 is O-R13, then R13 is not nitrogen-1-9C alkyl. Independent claims are also included for: (1) an electro-optical display or an electro-optical component comprising the above liquid crystalline medium; (2) preparing the liquid crystalline medium, comprising mixing (I) with (II), substituted bicyclohexyl compounds of formula (IVb) and/or substituted 1-cyclohexyl-2,3-difluorobenzene derivatives of formula (IIIa), substituted 1-cyclohex-1-enyl-2,3-difluorobenzene derivatives of formula (IIIb), substituted 2,3-difluoro-biphenyl derivatives of formula (IIIc) or substituted 2',3'-difluoro-[1,1';4',1'']terphenyl compounds of formula (IIId); and (3) stabilizing the liquid crystalline medium, comprising adding a medium which comprises (I) and optionally 2,6-di-tert-butyl-4-(4-propyl-cyclohexyl)-phenol, 2,6-di-tert-butyl-4-(5-propyl-[1,3]dioxan-2-yl)-phenol, 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, 3,5-di-tert-butyl-4-hydroxy-benzoic acid 4-pentyl-cyclohexylmethyl ester, 2,5-bis-(1,1,3,3-tetramethyl-butyl)-benzene-1,4-diol and acrylic acid 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methyl-benzyl)-4-methyl-phenyl ester to a medium which comprises (II). R31 : unsubstituted 1-7C alkyl; R32 : 1-7C alkyl or 1-6C alkoxy (both unsubstituted); m, n, o : 0 or 1; R51 : 1-7C alkyl or 2-7C alkenyl (both unsubstituted); and R52 : unsubstituted 2-7C alkenyl. [Image] [Image] [Image].
The Photodynamic Covalent Bond: Sensitized Alkoxyamines as a Tool to Shift Reaction Networks Out-of-Equilibrium Using Light Energy
Herder, Martin,Lehn, Jean-Marie
supporting information, p. 7647 - 7657 (2018/06/26)
We implement sensitized alkoxyamines as "photodynamic covalent bonds" - bonds that, while being stable in the dark at ambient temperatures, upon photoexcitation efficiently dissociate and recombine to the bound state in a fast thermal reaction. This type of bond allows for the photochemically induced exchange of molecular building blocks and resulting constitutional variation within dynamic reaction networks. To this end, alkoxyamines are coupled to a xanthone unit as triplet sensitizer enabling their reversible photodissociation into two radical species. By studying the photochemical properties of three generations of sensitized alkoxyamines it became clear that the nature and efficiency of triplet energy transfer from the sensitizer to the alkoxyamine bond as well as the reversibility of photodissociation crucially depends on the structure of the nitroxide terminus. By employing the thus designed photodynamic covalent bonding motif, we demonstrate how to use light energy to shift a dynamic covalent reaction network away from its thermodynamic minimum into a photostationary state. The network could be repeatedly switched between its minimum and kinetically trapped out-of-equilibrium state by thermal scrambling and selective photoactivation of sensitized alkoxyamines, respectively.
TEMPO-Mediated Oxidative Deformylation of Aldehydes: Applications in the Synthesis of Polyketide Fragments
Kipke, Andreas,Sch?ning, Kai-Uwe,Yusubov, Mekhman,Kirschning, Andreas
, p. 6906 - 6913 (2017/12/26)
A TEMPO-mediated oxidative deformylation of aldehydes is reported that yields the TEMPO adducts, which can be further oxidized to the corresponding ketones. The focus of this work was on the optimization of a synthetic protocol for use in natural product
Synthesis of cyclic (Co)polymers by atom transfer radical cross-coupling and ring expansion by nitroxide-mediated polymerization
Nicolay, Renaud,Matyjaszewski, Krzysztof
experimental part, p. 240 - 247 (2012/02/03)
A novel approach to prepare cyclic polymers via a combination of atom transfer radical polymerization (ATRP) and atom transfer radical cross-coupling (ATRC) is presented. A functional ATRP initiator possessing an alkoxyamine group was synthesized and used
Synthetic studies on N-alkoxyamines: A mild and broadly applicable route starting from nitroxide radicals and aldehydes
Schoening, Kai-Uwe,Fischer, Walter,Hauck, Stefan,Dichtl, Alexander,Kuepfert, Michael
supporting information; experimental part, p. 1567 - 1573 (2009/07/01)
A broad variety of 2,2,6,6-tetramethylpiperidine-based N-alkoxyamines were prepared in a newly found reaction. By means of a copper-catalyzed fragmentation reaction of aldehyde peroxides in the presence of TEMPO or TEMPO derivatives, N-alkoxyamines were o
PROCESS FOR THE PREPARATION OF STERICALLY HINDERED NITROXYL ETHERS
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Page/Page column 39, (2008/06/13)
The present invention relates to a novel process for the preparation of a sterically hindered nitroxyl ether from the corresponding sterically hindered nitroxyl radical by reacting it with a carbonyl compound and a hydroperoxide. The compounds prepared by this process are effective stabilizers for polymers against harmful effects of light, oxygen and/or heat, as flame-retardants for polymers and as polymerization regulators.
