1192-96-7Relevant articles and documents
Ambident Reactivity of Phenolate Anions Revisited: A Quantitative Approach to Phenolate Reactivities
Mayer, Robert J.,Breugst, Martin,Hampel, Nathalie,Ofial, Armin R.,Mayr, Herbert
, p. 8837 - 8858 (2019/07/08)
Prompted by the observation that the regioselectivities of phenolate reactions (C versus O attack) are opposite to the predictions by the principle of hard and soft acids and bases, we performed a comprehensive experimental and computational investigation of phenolate reactivities. Rate and equilibrium constants for the reactions of various phenolate ions with benzhydrylium ions (Aryl2CH+) and structurally related quinone methides have been determined photometrically in polar aprotic solvents. Quantum chemical calculations at the SMD(MeCN)/M06-2X/6-31+G(d,p) level confirmed that O attack is generally favored under kinetically controlled conditions, whereas C attack is favored under thermodynamically controlled conditions. Exceptions are diffusion-limited reactions with strong electrophiles, which give mixtures of products arising from O and C attack, as well as reactions with metal alkoxides in nonpolar solvents, where oxygen attack is blocked by strong ion pairing. The Lewis basicity (LB) and nucleophilicity (N, sN) parameters of phenolates determined in this work can be used to predict whether their reactions with electrophiles are kinetically or thermodynamically controlled and whether the rates are activation- or diffusion-limited. Comparison of the measured rate constants for the reactions of phenolates with carbocations with the Gibbs energies for single-electron transfer manifests that these reactions proceed via polar mechanisms.
Design, synthesis, insecticidal, and acaricidal activities of novel pyrimidinamine derivatives containing a biphenyl ether
Li, Lizhong,Zhou, Chunge,Liu, Minhua,Zhang, Ping,Zhang, Ning,Li, Jianming,Li, Tao,Liu, Xingping,Cheng, Shufen,Li, Qianhe,Liu, Aiping
, p. 3206 - 3214 (2019/11/13)
A series of original pyrimidinamine derivatives containing a biphenyl ether moiety were designed and synthesized. Their structures were confirmed by 1H NMR, MS, and elemental analyses. Their insecticidal activities against lepidopteran and hemiptera insects and acaricidal activities were tested. The results of bioassay demonstrated that 9k showed the best activity (LC50 = 2.08 mg/L) against Tetranychus urticae, which is comparable with the positive control, spirotetramat (LC50 = 2.27 mg/L), and 9g showed better activity (LC50 = 0.52 mg/L) against Aphis fabae than the positive control, imidacloprid (LC50 = 1.02 mg/L), and relatively good activity (LC50 = 2.49 mg/L) against T urticae. Their structure-activity relationships indicated that both an ethyl group on the 4-position of the pyrimidine ring and alkyl chain as a para-substituent group of the benzene ring showed good biological activity.
Impact of aryloxy initiators on the living and immortal polymerization of lactide
Chile,Ebrahimi,Wong,Aluthge,Hatzikiriakos,Mehrkhodavandi
, p. 6723 - 6733 (2017/07/10)
This report describes two different methodologies for the synthesis of aryl end-functionalized poly(lactide)s (PLAs) catalyzed by indium complexes. In the first method, a series of para-functionalized phenoxy-bridged dinuclear indium complexes [(NNO)InCl]2(μ-Cl)(μ-OPhR) (R = OMe (1), Me (2), H (3), Br (4), NO2 (5)) were synthesized and fully characterized. The solution and solid state structures of these complexes reflect the electronic differences between these initiators. The polymerization rates correlate with the electron donating ability of the phenoxy initiators: the para-nitro substituted complex 5 is essentially inactive. However, the para-methoxy variant, while less active than the ethoxy-bridged complex [(NNO)InCl]2(μ-Cl)(μ-OEt) (A), shows sufficient activity. Alternatively, aryl-capped PLAs were synthesized via immortal polymerization of PLA with A in the presence of a range of arylated chain transfer agents. Certain aromatic diols shut down polymerization by chelating one indium centre to form a stable metal complex. Immortal ROP was successful when using phenol, and 1,5-naphthalenediol. These polymers were analysed and chain end fidelity was confirmed using 1H NMR spectroscopy, MALDI-TOF mass spectrometry, and UV-Vis spectroscopy. This study shed light on possible speciation when attempting to generate PLA-lignin copolymers.
REACTION OF 6H-6-OXO--3(5)-HALOGENOANTHRAISOXAZOLES WITH INORGANIC NUCLEOPHILES
Gornostaev, L. M.,Zeibert, G. F.
, p. 1192 - 1194 (2007/10/02)
The reaction of 6H-6-oxo-3(5)-halogenoanthraisoxazoles with sodium azide in DMFA and also the potassium fluoride in acetonitrile in the presence of crown ethers leads to nucleophilic substitution of the halogen by the azide and fluoride ion respectively.
REACTION OF DIARYL ETHERS WITH ALKALI-METAL NITRITES
Plakhtinskii, V. V.,Ustinov, V. A.,Ryabukhina, N. S.,Mironov, G. S.,Kaninskii, P. S.
, p. 507 - 509 (2007/10/02)
The nucleophilic substitution of the aryloxy group in diaryl ethers by the nitrite ion leads to the formation of the corresponding substituted phenolates.The reaction rate increases with increase in the electron-withdrawing characteristics of the substituents both in the ring in which substitution occurs and in the leaving aryloxy group.
