787-07-5Relevant articles and documents
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Wood,G.,Woo,E.P.
, p. 3713 - 3717 (1968)
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Ultra-fast rotors for molecular machines and functional materials via halogen bonding: Crystals of 1,4-bis(iodoethynyl)bicyclo[2.2.2]octane with distinct gigahertz rotation at two sites
Lemouchi, Cyprien,Vogelsberg, Cortnie S.,Zorina, Leokadiya,Simonov, Sergey,Batail, Patrick,Brown, Stuart,Garcia-Garibay, Miguel A.
, p. 6371 - 6379 (2011)
As a point of entry to investigate the potential of halogen-bonding interactions in the construction of functional materials and crystalline molecular machines, samples of 1,4-bis(iodoethynyl)bicyclo[2.2.2]octane (BIBCO) were synthesized and crystallized. Knowing that halogen-bonding interactions are common between electron-rich acetylenic carbons and electron-deficient iodines, it was expected that the BIBCO rotors would be an ideal platform to investigate the formation of a crystalline array of molecular rotors. Variable temperature single crystal X-ray crystallography established the presence of a halogen-bonded network, characterized by lamellarly ordered layers of crystallographically unique BIBCO rotors, which undergo a reversible monoclinic-to-triclinic phase transition at 110 K. In order to elucidate the rotational frequencies and the activation parameters of the BIBCO molecular rotors, variable-temperature 1H wide-line and 13C cross-polarization/magic-angle spinning solid-state NMR experiments were performed at temperatures between 27 and 290 K. Analysis of the 1H spin-lattice relaxation and second moment as a function of temperature revealed two dynamic processes simultaneously present over the entire temperature range studied, with temperature-dependent rotational rates of krot = 5.21 × 1010 s-1·exp(-1.48 kcal·mol -1/RT) and krot= 8.00 × 1010 s -1·exp(-2.75 kcal·mol-1/RT). Impressively, these correspond to room temperature rotational rates of 4.3 and 0.8 GHz, respectively. Notably, the high-temperature plastic crystalline phase I of bicyclo[2.2.2]octane has a reported activation energy of 1.84 kcal·mol-1 for rotation about the 1,4 axis, which is 24% larger than Ea = 1.48 kcal·mol-1 for the same rotational motion of the fastest BIBCO rotor; yet, the BIBCO rotor has three fewer degrees of translational freedom and two fewer degrees of rotational freedom! Even more so, these rates represent some of the fastest engineered molecular machines, to date. The results of this study highlight the potential of halogen bonding as a valuable construction tool for the design and the synthesis of amphidynamic artificial molecular machines and suggest the potential of modulating properties that depend on the dielectric behavior of crystalline media.
Synthesis of 4 - carboxymethyl cyclohexane carboxylic acid of the new method (by machine translation)
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Paragraph 0005; 0019-0021, (2017/10/07)
The invention relates to a method for the synthesis of the compounds. Synthesis of 4 - carboxymethyl cyclohexane carboxylic acid of the new method, 1st step succinyl ding acid diethyl ester synthesis: to sodium hydride, tertiary butyl alcohol and succinic acid diethyl ester as the raw material to make the succinyl ding acid diethyl ester; 2nd step synthesis of intermediate I: to sodium hydride, succinyl ding succinic acid ester and 1, 2 - Dibromoethane as raw materials get intermediate I; 3rd step products 1 and 2 synthesis: in the reaction kettle to join the intermediate I, potassium hydroxide, ethanol and water, reflux reaction to obtain the intermediate I of the potassium salt; take another in the reactor after the adding of the potassium salt, potassium hydroxide, hydrazine hydrate, ethylene glycol, heating reflux reaction, to obtain the solid 4 - carboxymethyl cyclohexane carboxylic acid product 1, most of the mother liquor in the product 2. The invention synthetic route is reasonable in design, brief, gathers warm reaction conditions, easy operation, low cost and easy availability of raw materials, the products made good selectivity, easy product separation, has the advantages of high yield and purity. (by machine translation)
Synthesis of Substituted 3(2H)-Furanones Using Alkylative Intramolecular Cyclization of Sulfonium Salts
Inagaki, Sho,Ukaku, Mika,Chiba, Akira,Takahashi, Fumi,Yoshimi, Yasuharu,Morita, Toshio,Kawano, Tomikazu
, p. 8363 - 8369 (2016/09/28)
The facile alkylative intramolecular cyclization of 3-alkoxycarbonyl-2-oxopropyldiphenylsulfonium salts is described. This simple method can be readily applied to the synthesis of a novel family of 4-alkylated 3(2H)-furanones in moderate to high yields under mild conditions via a one-pot process.
