- Preparation method 1, 1 - dibromo -2, 2 -bis (chloromethyl) cyclopropane
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The invention provides a preparation method of 1, 1 - dibromo -2 and 2 -bis (chloromethyl) cyclopropane. , A reaction starting system containing 3 - chlorine -2 - chloromethyl propylene is added, reactants for generating dibromocarbene are added at the same time, and dibromocarbene is generated in real time. , Based on addition reaction of dibromocarbene and 3 - chlorine -2 - chloromethyl propylene, a target product is generated in real time. The method provided by the invention can ensure that the real-time generated dibromocarb and 3 - chlorine -2 - chloromethyl propylene react in time, so that the reaction time is shortened, and the yield is improved. On the other hand, the amount of reactants can be maintained at a lower level to reduce the generation of by-products, increasing the purity. In addition, the method can also avoid massive precipitates in the reaction system, so that the reaction is more sufficient, the reaction time is further shortened, the yield and the purity are improved, the post-treatment difficulty and cost are reduced, and the applicability of industrial production is improved.
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Paragraph 0064; 0086; 0090-0147
(2021/10/05)
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- Synthetic method of 1,1-dibromo-2,2-dual(chloromethyl)-cyclopropane
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The invention discloses a synthetic method of 1,1-dibromo-2,2-dual(chloromethyl)-cyclopropane. The method comprises the following steps that chlorine substitution reaction happens to 2-amino-2-hydroxylmethylpropane-1,3-diol to obtain (1,3-dichloro-2-(chloromethyl)propane-2-group)amino-sulfone-ketone; the (1,3-dichloro-2-(chloromethyl)propane-2-group)amino-sulfone-ketone is hydrolyzed through a concentrated sulfuric acid aqueous solution to obtain 1,3-dichloro-chloromethylpropyl-2-amine-sulfate; the 1,3-dichloro-chloromethyl-propyl-2-amine-sulfate is subjected to salt dissolution on the alkaline condition, and is subjected to cyclization to form 2,2-dual(chloromethyl)aziridine; reaction happens to 2,2-dual(chloromethyl)aziridine and sodium nitrite to form 3-chloro-2-chloromethyl-propyl-1-alkene; and the 3-chloro-2-chloromethyl-propyl-1-alkene reacts with bromoform on the alkaline condition to generate 1,1-dibromo-2,2-dual(chloromethyl)-cyclopropane. The synthetic method of 1,1-dibromo-2,2-dual(chloromethyl)-cyclopropane is simple and can be used for enlarged production.
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Paragraph 0037-0038; 0044
(2020/02/17)
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- CONTINUOUS FLOW PROCESSES FOR MAKING BICYCLIC COMPOUNDS
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Processes for making bicyclic compounds and precursors thereof, and particularly for making [1.1.1]propellane and bicyclo[1.1.1]pentane and derivatives thereof, utilize continuous flow reaction methods and conditions. A continuous process for making [1.1.1]propellane can be conducted under reaction conditions that advantageously minimize clogging of a continuous flow reactor. A continuous flow process can be used to make precursors of [1.1.1]propellane.
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Paragraph 0102
(2019/04/10)
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- Preparation method for bicyclo [1.1.1] pentane-1,3-dicarboxylic acid dimethylester
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The invention relates to a preparation method for bicyclo [1.1.1] pentane-1,3-dicarboxylic acid dimethylester, and mainly solves the technical problem that a method suitable for industrial synthesis does not exist at present. The preparation method comprises the following six steps: firstly, reacting a compound (1) and bromoform under an alkaline condition to obtain a compound (2); secondly, reacting the compound (2) and lithium methide to obtain a compound (3); thirdly, illuminating the compound (3) and diacetyl by a high-pressure mercury lamp to obtain a compound (4); fourthly, treating with sodium hypochlorite to obtain a compound (5); fifthly, reacting the compound (5) and thionyl chloride to obtain a compound (6); and finally, treating the compound (6) under the effect of methanol to obtain a compound (7) which is a final product. A reaction formula is as shown in the specification, and the acquired bicyclo [1.1.1] pentane-1,3-dicarboxylic acid dimethylester is a useful midbody or product for synthesis of many drugs.
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Paragraph 0006; 0007
(2017/03/08)
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- FUSED FURANS FOR THE TREATMENT OF HEPATITIS C
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The disclosure provides compounds of formula I or II, including their salts, as well as compositions and methods of using the compounds. The compounds have activity against hepatitis C virus (HCV) and may be useful in treating those infected with HCV. [
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Page/Page column 66-67
(2014/10/15)
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- 1,3-Diethynylbicyclo[1.1.1]pentane, a useful molecular building block
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1,3-Diethynylbicyclo[1.1.1]pentane (DEBCP) has been found to be a valuable molecular building block mostly for the synthesis of extended, rigid, rod-like molecules. With its straightforward linear geometry, DEBCP can be used as a nonconjugated alternative to more frequently used π-conjugated, rod-like building blocks. Examples of reactions that introduce DEBCP into larger structures are (1) the reaction of DEBCP lithium acetylides with electrophiles such as TMSCl, CO2, and Ph2PCl, (2) Sonogashira-Hagihara cross-coupling reactions with aryl or heteroaryl iodides or bromides, and (3) umpolung reactions that afford the corresponding dibromo and diiodo derivatives of DEBCP, which then successfully react with tert-C-cuprates derived from p- and m-dicarbadodecaboranes or bicyclopentanes. These umpolung reactions afforded a new class of molecular rods that combine carborane or bicyclo[1.1.1]pentane cages with ethynylene linkers. Many of the DEBCP derivatives were studied by single-crystal X-ray diffraction. They form well-organized arrays of molecular rotors, the DEBCP units, and so can be considered as examples of artificial molecular-size machines. Copyright
- Kaleta, Jiri,Necs, Marek,Mazal, Ctibor
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scheme or table
p. 4783 - 4796
(2012/09/22)
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- 1,3-bicyclo[1.1.1]pentanediyl: The shortest rigid linear connector of phenylated photochromic units and a 1,5-dimethoxy-9,10-di(phenylethynyl) anthracene fluorophore
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An excess of bis-1,3-(4-iodophenyl)bicyclo[1.1.1]pentane, prepared in 63% yield by iodination of 1.3-diphenylbicyclo[1.1.1]pentane, was selectively mono-coupled with 9-ethynyl-1,5-dimethoxy-10-phenylethynylanthracene (26), and subsequently with the zinc derivatives of 1-(2-methyl/methoxy-4-methyl-5- phenylthiophen-3-yl)-2-(2-methyl/methoxy-4-methylthiophen-3-yl) perfluorocyclopentenes (38-H-41-H). Regioselective synthesis of the 2-unsubslituted thiophenes 38-H-41-H required intermediate prepara tion of 2-trimethylsilyl-3,5-dimethyl-4-bromothiophene (37) or 2-trimethylsilyl-5- methoxy-3-methyl-4-bromothiophene (40). Protection of the α-position of the thiophene ring with a 2-trimethylsilyl group blocks the rearrangement of the 4-lithio derivatives into the corresponding 2-lithiated thiophenes. With the bicyclo[1.1.1]pentane frag ment linking the photochromic units 1-3 and 1,5-dimethoxy-9,10-di(phenylethynyl)anthracene as a fluorescent part, quantitative resonance energy transfer between the excited state of the fluorophore (donor) and the closed form of the photochromic units 1-3 (acceptors) was observed. The closed forms of the methoxy-substituted photochromic units 2 and 3 are less resistant to UV light (313 nm) than the closed form of 1.
- De Meijere, Armin,Ligang, Zhao,Belov, Vladimir N.,Bossi, Mariano,Noltemeyer, Matthias,Hell, Stefan W.
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p. 2503 - 2516
(2008/04/01)
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- Compounds and methods based on [1.1.1]propellane
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Molecular bulding beams, liquid crystals, and surfactants in the form of compounds based on [1.1.1]propellane, including poly[1.1.1]propellanes. Molecular building beams having a telomeric or polymeric chain staff, and linking groups functionalized on one or both ends of the staff. A system for linking the beams to connecting units to construct molecular structures of various forms, such as whips, combs, scaffoldings, nets, or stars. Other broad aspects of the invention provide liquid crystals and surfactants. The liquid crystals include telomeric or polymeric compounds functionalized with flexible end groups, while the surfactant compounds are functionalized with surface active end groups. Methods of synthesizing the various compounds ar also provided.
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- Synthesis of Some Bridgehead-Bridgehead-Disubstituted Bicyclopentanes
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The synthesis of a wide variety of 1,3-disubstituted bicyclopentanes is described, with particular emphasis on the generation of a series of 3-X-substituted bicyclopentyl bromides required for solvolytic studies.Functional group manipulation at the bridgehead was readily accomplished in the majority of cases by radical processes; in some instances, transformations were effected via carbanionic-type intermediates.
- Della, Ernest W.,Taylor, Dennis K.
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p. 2986 - 2996
(2007/10/02)
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- Toward a molecular-size "Tinkertoy" construction set. Preparation of terminally functionalized [n]staffanes from [1.1.1]propellane
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A facile but low-yield synthesis of [n]staffanes (the oligomers of [1.1.1.]propellane 1, n =1-5) functionalized on one or both ends is described, and their properties are summarized. The substituents are -COOCH3, -n-C4H9, -C6H5, -Br, -I, and -SCOCH3, and their conversion to others, such as -COOH, -COCH3 and -SH, is demonstrated. It is proposed that these rod-shaped molecules will be useful in the development of a molecular-size civil engineering construction set analogous to children's toy construction sets.
- Kaszynski, Piotr,Friedli, Andrienne C.,Michl, Josef
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p. 601 - 620
(2007/10/02)
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- Concerning the Synthesis of Propellane
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The reaction of 1,1-dibromo-2,2-bis(chloromethyl)cyclopropane (2) with methyllithium in ether led to a solution of propellane (1) in a yield of 70percent. 1 could also be prepared free of solvent by reaction of 2 with lithium powder in triglyme/n-decane at 73 deg C. - Keywords: Cyclopropa annulation/ Propellane/ Polycycles, strained
- Belzner, Johannes,Bunz, Uwe,Semmler, Klaus,Szeimies, Guenter,Opitz, Klaus,Schlueter, Arnulf-Dieter
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p. 397 - 400
(2007/10/02)
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