Results 71 to 80 of about 67,257 (300)
Trimethylsilyl Substituent Effects on the Triazolium-catalysed Benzoin Condensation [PDF]
, 2021 In the benzoin condensation catalysed by N-heterocyclic carbenes (NHCs) there exists a unique 2-substituent effect. 2-Substituted aldehydes with 2-Lewis basic substituents will preferentially take part in the first addition step of NHC to aldehyde ...
MACRAE, HECTOR,IAN
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Advanced Materials, EarlyView.Atomically precise functionalization by N‐heterocyclic carbenes enhances the catalytic efficiency of macroscopically defined step edges toward electrochemical CO2${\rm CO}_2$ reduction. Sub‐molecular imaging reveals conformational differences between specific NHCs, which can be correlated with their catalytic performance. Photoelectron spectroscopy and
Philipp Wiesener +9 more
wiley +1 more source
Structural Analysis of 3,5-Bistrifluoromethylhydrocinnamic Acid
CrystalsThe crystal structure of 3,5-bistrifluoromethylhydrocinnamic acid [systematic name: 3-[3,5-bis(trifluoromethyl)phenyl]propanoic acid], C11H8F6O2, has been determined and described.
Piotr F. J. Lipiński, Krzysztof Łyczko
doaj +1 more source
New description of the substituent effect on electronic spectra by means of substituent constants
Journal of Molecular Structure: THEOCHEM, 1991 著者らは近年,電子スペクトルに対する置換基効果を置換基定数で記述する新しい方法を研究してきた。電子スペクトルで測定される一重項あるいは三重項遷移エネルギー(1.3Euv)は, Swain らの FR 置換基定数あるいは湯川らの置換基定数 (σi ,σπ+,σπ-)を用いて, 1.3EUV=aF+bR+C, 1,3EUV=ασi+βσπ++γσπ-+Cと記述された。そして,これらは共役系の n-π* 吸収帯を初め,共役系および脂肪族系の n-π* 吸収帯,分子内電荷移動吸収帯,分子化合物の分子間電荷移動吸収帯およびそれら錯体形成による成分化合物自身の吸収帯などに対する置換基効果に適用できる一般式であることを明らかにした。さらに,ベンゼン置換体の吸収帯を用いて,これらの式の適用限界を議論した ...
Bunji UNO, Tanekazu KUBOTA
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New quantum chemical parameter for the substituent effect in benzene based on charge flux
, 2018 Charge distributions determining the electrostatic potential in monosubstituted benzenes are investigated. As a result, a new quantum chemical parameter for substituent effect, which would be useful in information coding (in terms of molecular ...
Lee, JY, Mhin, BJ, Kim, KS
core +1 more source
Advanced Materials, EarlyView.A dual‐additive electrolyte strategy is developed to address the hydrolysis of I+ in the aqueous electrolytes. The steric‐hindrance effect of TES− effectively shields I+ from nucleophilic attacks by hydroxyl groups, facilitating the reversible I−/I0/I+ conversion with four‐electron transfer.
Shuai Wang +8 more
wiley +1 more source
Effect of Substituent on Ionisation of Saturated Fatty Acids
, 1964 The length of tho carbon chain of a fatty acid molecule has been found to have little effect on the ionieation of the unsubstituted acid. Decided changes in pK values are observed when a substituent is introduced into the moleclue.
S. C. Rakshit and S. Guha
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Light Switchable Ionic Conductivity of Arylazopyrazole Modified Polysiloxanes
Advanced Materials Technologies, EarlyView.We present a polysiloxane functionalized with a novel arylazopyrazole dye that undergoes reversible photoisomerization. Upon lithium bis(trifluoromethanesulfonyl)imide addition and UV irradiation, the polymer exhibits a shift in tan(d) toward higher frequencies and enhanced ionic conductivity.
Malte S. Beccard +7 more
wiley +1 more source
Molecules, 2018 The fac-Ir(ppy)3 complex, where ppy denotes 2-phenylpyridine, is one of the well-known luminescent metal complexes having a high quantum yield. However, there have been no specific molecular design guidelines for color tuning.
Yoshiki Natori +6 more
doaj +1 more source
Influência de efeitos estéricos na hidrólise ácida de o-alquil acetais do benzaldeído [PDF]
, 2003 Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-Graduação em Química.Investigação de efeitos estéricos sobre o centro reacional na hidrólise ácida de O-alquil acetais do benzaldeído ...
Belarmino, Alexanders Tadeu das Neves
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