1522-92-5Relevant articles and documents
Synthesis and copolymerization of azidomethyl-substituted oxetanes: the morphology of statistical block copolymers
Mukhametshin, Timur I.,Petrov, Aleksei I.,Kuznetsova, Nina V.,Petrov, Vladimir A.,Averianova, Natalia V.,Garaev, Ilgiz Kh.,Kostochko, Anatoly V.,Gubaidullin, Aidar T.,Vinogradov, Dmitry B.,Bulatov, Pavel V.
, p. 811 - 821 (2017)
[Figure not available: see fulltext.] 3,3-Bis(azidomethyl)oxetane and 3-azidomethyl-3-methyloxetane were obtained by bromination of pentaerythritol and metriol with a mixture of hydrobromic, acetic, and sulfuric acids, followed by cyclization in the presence of a phase-transfer catalyst TBAB, with the formation of oxetane ring and replacement of bromide substituents with azide ions. The copolymerization reaction of 3,3-bis-(azidomethyl)oxetane and 3-azidomethyl-3-methyloxetane was performed in the presence of a catalytic system prepared from triisobutylaluminum and water. The methods of small-angle and wide-angle X-ray diffraction analysis were used to determine the amorphous-crystalline and domain structures of the synthesized copolymers. We also present data about conformational and relaxation transitions in these statistical copolymers.
Altering the specificity of subtilisin Bacillus lentus through the introduction of positive charge at single amino acid sites
Davis, Benjamin G.,Khumtaveeporn, Kanjai,Bott, Richard R.,Jones, J.Bryan
, p. 2303 - 2311 (1999)
The use of methanethiosulfonates as thiol-specific modifying reagents in the strategy of combined site-directed mutagenesis and chemical modification allows virtually unlimited opportunities for creating new protein surface environments. As a consequence
Saucier et al.
, p. 1599,1600 (1966)
Preparation method of trisbromoneopentyl alcohol
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Paragraph 0010; 0023-0030, (2020/04/02)
The invention provides a preparation method of trisbromoneopentyl alcohol. The method taking pentaerythritol, bromine and sulfur powder as raw materials comprises the following steps: reducing bromineby taking the sulfur powder as a reducing agent to generate hydrogen bromide in situ, carrying out a heating reaction on the hydrogen bromide and an organic acid used as a solvent, carrying out reduced pressure distillation after the reaction is finished to recover acetic acid and hydrogen bromide, performing alcoholysis by using methanol, carrying out reduced pressure distillation to recover methanol and methyl acetate, adding an aqueous sodium carbonate solution to neutralize generated sulfuric acid, adding water and alkane, performing liquid separation, and performing cooling crystallization on the obtained organic phase to obtain high-purity trisbromoneopentyl alcohol. Compared with preparation methods which are publicly reported at present, the preparation method for preparing the trisbromoneopentyl alcohol from hydrogen bromide generated in situ by reducing bromine with the sulfur powder has the advantages of few side reactions, low cost, high yield of 90% or above, realizationof the product purity of 99.5% or above, simplicity in operation, and facilitation of industrial production.
A three-the bromine is new pentanol synthetic method
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Paragraph 0022; 0023; 0024; 0025; 0026; 0027-0037, (2017/08/25)
The invention relates to a synthetic method of trisbromoneopentyl alcohol. The synthetic method comprises: adding pentaerythritol in an inert solvent; adding phosphorous tribromide for substitution reaction; performing under-pressure distillation to remove the solvent after the reaction is over and obtaining trisbromoneopentyl alcohol ester; adding methanol into trisbromoneopentyl alcohol ester for transesterification; performing distillation to remove redundant methanol after transesterification is over; washing the obtained product till the pH value of a filtering liquid is 7 to obtain crude trisbromoneopentyl alcohol; and performing recrystallization of crude trisbromoneopentyl alcohol by using a mixed solvent of methanol and water to obtain pure trisbromoneopentyl alcohol. Compared to a conventional synthetic method, the method in the invention has characteristics, such as available raw materials, simple preparation technology, high synthetic yield, and less by-product.
