40145-10-6Relevant academic research and scientific papers
Modulation of Electronic Coupling through Self-Assembled Monolayers via Internal Chemical Modification
Cheng, Jun,Saghi-Szabo, Gotthard,Tossell, John A.,Miller, Cary J.
, p. 680 - 684 (1996)
Self-assembled monolayers of ω-hydroxyalkanethiols at Au electrodes are used to probe the structural dependence of long-range electron transfer.The electron transfer rates for ferricyanide and osmium(III) tris(bipyridyl) are measured at Au electrodes coated with self-assembled monolayers of HO(CH2)n-X-(CH2)mSH where X denotes an ether, olefin, or alkyne function.Each of these modifications decreases the electronic coupling across the monolayers.Ab initio calculations of the neutral diradical splitting energies for modified and unmodified alkanes correctly predict these decreases in electronic coupling.
Straightforward Synthesis of Fluorinated Enals via Photocatalytic α-Perfluoroalkenylation of Aldehydes
Wulkesch, Christian,Czekelius, Constantin
, p. 7425 - 7438 (2021/06/21)
(Per)fluorinated substances represent an important compound class with regard to drug design and material chemistry. We found a mild, operationally simple, and inexpensive photocatalytic perfluoroalkenylation reaction giving tetrasubstituted, highly electron-deficient enals straight from aldehydes. This one-step reaction tolerates various functional groups and can be applied to a wide range of substrates giving the products in yields of 52-84%.
Nickel-Catalyzed Formal Aminocarbonylation of Unactivated Alkyl Iodides with Isocyanides
Chen, Yifeng,Huang, Wenyi,Qu, Jingping,Shrestha, Mohini,Wang, Yun,Weng, Yangyang
supporting information, p. 3245 - 3250 (2020/04/21)
Herein, we disclose a Ni-catalyzed formal aminocarbonylation of primary and secondary unactivated aliphatic iodides with isocyanides to afford alkyl amide, which proceeds via the selective monomigratory insertion of isocyanides with alkyl iodides, subsequent β-hydride elimination, and hydrolysis process. The reaction features wide functional group tolerance under mild conditions. Additionally, the selective, one-pot hydrolysis of reaction mixture under acid conditions allows for expedient synthesis of the corresponding alkyl carboxylic acid.
Transition-Metal-Free Borylation of Alkyl Iodides via a Radical Mechanism
Liu, Qianyi,Hong, Junting,Sun, Beiqi,Bai, Guangcan,Li, Feng,Liu, Guoquan,Yang, Yang,Mo, Fanyang
supporting information, (2019/07/08)
We describe an operationally simple transition-metal-free borylation of alkyl iodides. This method uses commercially available diboron reagents as the boron source and exhibits excellent functional group compatibility. Furthermore, a diverse range of prim
Cycloaddition Reactions of Cobalt-Complexed Macrocyclic Alkynes: The Transannular Pauson-Khand Reaction
Karabiyikoglu, Sedef,Boon, Byron A.,Merlic, Craig A.
, p. 7732 - 7744 (2017/08/14)
The Pauson-Khand reaction is a powerful tool for the synthesis of cyclopentenones through the efficient [2 + 2 + 1] cycloaddition of dicobalt alkyne complexes with alkenes. While intermolecular and intramolecular variants are widely known, transannular versions of this reaction are unknown and the basis of this study. Macrocyclic enyne and dienyne complexes were readily synthesized by palladium(II)-catalyzed oxidative macrocyclizations of bis(vinyl boronate esters) or ring-closing metathesis reactions followed by complexation with dicobalt octacarbonyl. Several reaction modalities of these macrocyclic complexes were uncovered. In addition to the first successful transannular Pauson-Khand reactions, other intermolecular and transannular cycloaddition reactions included intermolecular Pauson-Khand reactions, transannular [4 + 2] cycloaddition reactions, intermolecular [2 + 2 + 2] cycloaddition reactions, and intermolecular [2 + 2 + 1 + 1] cycloaddition reactions. The structural and reaction requirements for each process are presented.
Application of "click" chemistry in solid phase synthesis of alkyl halides
Das, Diparjun,Chanda, Tridib,Rokhum, Lalthazuala
, p. 775 - 783 (2016/01/20)
A convenient and highly selective microwave assisted procedure for the conversion of allylic, benzylic and aliphatic alcohols to their corresponding halides using polymer-bound triphenylphosphine and iodine is presented. In case of symmetrical diols, mono-iodination product is obtained in very high yield. Additionally, highly regioselective behavior is observed in our procedure. Simplicity in operation, no column chromatography required for the purification of the products, recyclability of the reagents used, short reaction times and good to excellent yields are the advantages of our protocol. Most functional groups remain unaffected under our reaction condition.
Synthesis, structure, and properties of chiral liquid crystal monomers and polymers based on menthol
Hu, Jian-She,Li, Dan,Zhang, Wen-Chang,Meng, Qing-Bao
, p. 5049 - 5059 (2013/01/15)
To study structure-mesomorphism relationships of the monomers and polymers based on menthol, four new chiral monomers (M1-M4) and the corresponding homopolymers (P1-P4) with menthyl group were synthesized. Their chemical structures, formula, phase behavior, and thermal stability were characterized by FTIR, 1H NMR, 13C NMR, elemental analyses, differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, and thermogravimetric analysis. The selective reflection of light was investigated with ultraviolet/visible spectrometer. The influence of the mesogenic core rigidity, spacer length, and menthyl steric effect on the mesomorphism of M1-M4 and P 1-P4 was examined. By inserting a flexible spacer between the mesogenic core and the terminal menthyl groups, four target monomers and polymers could form the expected mesophase. Moreover, their melting temperature (Tm), glass transition temperature (Tg), clearing temperature (Ti), and mesophase range (δT) increased with increasing the mesogenic core rigidity; whereas the Tm and T g decreased, Ti and δT increased with an increase of the spacer length. M1 and M2 showed monotropic and enantiotropic cholesteric phase, respectively, whereas M3 and M 4 all revealed chiral smectic C (SmC*), cholesteric and cubic blue phases. In addition, with increasing temperature, the selective reflection of light shifted to the long wavelength region at the SmC* phase range and to the short wavelength region at the cholesteric range, respectively. P 1 and P2 only showed a smectic A (SmA) phase, whereas P3 and P4 exhibited the SmC* and SmA phases. All the obtained polymers had very good thermal stability.
Synthesis and physical properties of ferrocene derivatives (XXV) liquid crystallinity of 1,3-disubstituted ferrocene derivatives
Nakamura, Naotake,Kagawa, Shinya
experimental part, p. 150 - 159 (2012/01/03)
Liquid crystallinity of 1,3-disubstituted ferrocene derivatives was studied by DSC and polarizing microscope. The name of the derivatives is 1,3-bis[-[4-(4-methoxyphenoxycarbonyl)phenoxy]alkyloxycarbonyl]ferrocene. Nine members from n = 2 to 10 were synthesized (n is carbon number of alkyl chain in the sample). All samples except n = 2 and 4 exhibited monotropic nematic liquid crystalline phase. In addition, smectic X (not yet completely identified) was also observed in n = 8 and 10. Liquid crystalline phase transition phenomena were discussed from a viewpoint of molecular shape. Copyright Taylor & Francis Group, LLC.
One-pot click synthesis of 1N-alkyl-4-aryl-1,2,3-triazoles from protected arylalkynes and alkyl bromides
Ladouceur, Sebastien,Soliman, Ahmed M.,Zysman-Colman, Eli
supporting information; experimental part, p. 3604 - 3611 (2011/12/16)
1N-Alkyl-4-aryl-1,2,3-triazoles have been prepared through a multicomponent one-pot protocol from the corresponding (arylethynyl)trimethylsilanes and alkyl bromides. In situ alkyl azide formation and alkyne deprotection followed by copper(I)-catalyzed click cycloaddition afforded the desired 1,4-disubstituted 1,2,3-triazoles in generally good to excellent yield, with only minor observation of the undesired 1,5-regioisomeric cycloadduct. The protocol eliminates the need to use reactive organic azides and terminal alkynes. Georg Thieme Verlag Stuttgart. New York.
Synthesis and physical properties of ferrocene derivatives (XXIII): Phase transition and unique molecular structure of monosubstituted ferrocene derivatives
Nakamura, Naotake,Hiro, Kazuya,Nishikawa, Masako,Okabe, Takashi,Uno, Kenjiro
scheme or table, p. 122 - 131 (2010/08/05)
The monosubstituted ferrocene derivatives, -[4-(4-methoxyphenoxycarbonyl) phenoxy]alkoxycarbonyl ferrocene, were synthesized in order to compare the liquid crystallinity to that of disubstituted ferrocene derivatives, 1,1'-bis[-[4-(4-methoxy-phenoxycarbonyl)phenoxy]alkoxycarbonyl]ferrocene. Some of the monosubstituted ferrocene derivatives containing relatively longer flexible spacer showed the liquid crystalline phase, nematic and/or smectic phases. The crystal structure of 2-[4-(4-methoxyphenoxycarbonyl)phenoxy] ethoxycarbonyl ferrocene was determined by X-ray diffraction method using a single crystal. The molecular structure revealed a bent structure that is almost a half of "Z" shaped molecular structure of 1,1'-bis[2-[4-(4- methoxyphenoxycarbonyl)phenoxy]ethoxycarbonyl]ferrocene.
