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11.
Vasundhara Singh Rakesh Vig Vishv Mohini I. R. Trehan G. L. Kad 《Journal of Chemical Sciences》1992,104(1):57-60
Syntheses of (4E,6E,11Z)-4,6,11-hexadecatrienyl acetate (1) and (4E,6E, 11Z)-4, 6,11-hexadecatrienal (2), female sex pheromones of eri-silkworm,Samia cynthia ricini have been achieved through Claisen ortho ester rearrangement of (6). 相似文献
12.
Abdullah Karanfil 《合成通讯》2017,47(24):2342-2351
Practical and economical synthesis of synthetically valuable 3,3,3-triethoxypropyne, ketal protected phenyl and methyl substituents prop-2-ynones is described. Bromination and subsequent 18-crown-6 catalyzed elimination of triethylorthoacrylate and ketal protected terminal alkenes with methyl and phenyl substituent which are inturn readily available from triethylorthopropionate, 3-chlorobutan-2-one and propiophenone afforded multigram quantities (>10?g) of corresponding functionalized terminal alkynes. Exploration of the synthetic utility of these alkynes is also demonstrated by the acetylenic substitution of the phenylalaninol derived 1,2-cyclic sulfamidate to deliver chiral alkynylated amines. 相似文献
13.
Haruo Nishida Fumio Sanda Takeshi Endo Takeshi Nakahara Takayuki Ogata Koshi Kusumoto 《Journal of polymer science. Part A, Polymer chemistry》1999,37(24):4502-4509
The addition reaction of spiro orthoesters (SOEs) with electrophiles accompanying ring-opening isomerization was investigated as a model reaction for polyaddition of bifunctional SOEs with bifunctional electrophiles. Among several electrophiles such as carboxylic acids and carboxylic anhydrides, acid halides showed particularly high reactivities to SOEs. An equimolar reaction of SOEs with acid chlorides took place selectively, leading to the corresponding 1 : 1 adducts. SOEs with seven-membered cyclic ether rings—1,4,6-trioxaspiro[5.6]undecane derivatives—showed higher reactivities than SOEs with six- and five-membered cyclic ether rings. The reaction accompanied zero shrinkage in volume. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4502–4509, 1999 相似文献
14.
Kiyoko Yoshida Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(14):2551-2558
A spiro orthoester having an ester moiety, 2-acetoxymethyl-1,4,6-trioxaspiro[4.6]undecane (4) was synthesized, and its cationic polymerization and depolymerization of the obtained polymer (5) were carried out. The monomer 4 underwent cationic polymerization with a cationic catalyst to afford the corresponding poly(cyclic orthoester) 5. The obtained polymer 5 could be depolymerized with a cationic catalyst to regenerate the monomer 4 in an excellent yield. Further, bifunctional spiro orthoesters (6, 8, 9) having diester moieties were synthesized from terephthalic acid, succinic acid, and 1,4-cyclohexanedicarboxylic acid, and their acid-catalyzed reversible crosslinking–decrosslinking was examined. The bifunctional monomer 6 derived from terephthalic acid underwent cationic crosslinking to afford the corresponding network polymer (7), which could be also depolymerized to regenerate the original bifunctional monomer 6. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2551–2558, 1999 相似文献
15.
Haruo Nishida Fumio Sanda Takeshi Endo Takeshi Nakahara Takayuki Ogata Koshi Kusumoto 《Journal of polymer science. Part A, Polymer chemistry》2000,38(1):68-73
Polyaddition of bifunctional spiro orthoesters (SOEs) with bifunctional acid chlorides was examined to develop zero‐shrinkage polymerization. The polyaddition afforded the corresponding polyether‐esters by repeating the addition reaction accompanying the double ring‐opening isomerization of the SOE moiety in a manner similar to the reaction of monofunctional SOEs with acid chlorides. The polyaddition accompanied a slight shrinkage or expansion in volume. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 68–73, 2000 相似文献
16.
Subhash P Chavan Cherukupally Praveen G Ramakrishna U.R Kalkote 《Tetrahedron letters》2004,45(31):6027-6028
An efficient synthesis of α-lipoic acid from the readily available cis-2-butene-1,4-diol employing a Claisen orthoester rearrangement and Sharpless asymmetric dihydroxylation as the key steps, is described. 相似文献
17.
18.
螺环原酸酯改性环氧树脂的研究 总被引:1,自引:0,他引:1
合成了一个新的螺环原酸酯单体,即带有螺环原酸酯结构单元的环氧树脂(E 54).用该单体对环氧树脂进行改性,可以减少残留在树脂基体中的环氧基团,这说明该单体与环氧树脂之间发生了共聚固化反应.基体的Tg和热稳定性随预聚物加入量的增加而降低,但改性环氧树脂的粘接强度则随预聚物的加入量的增加而增加.对上述试验观察到的现象进行了讨论,并测试了改性环氧树脂基体的力学性能. 相似文献
19.
Magnetically recoverable Fe3O4 nanoparticles have been synthesized as a catalyst for the cyclocondensation of 1,2-phenylenediamines with orthoesters under solvent-free conditions.Catalyst loadings can be as low as 1 mol% to give high yields of the corresponding benzimidazole derivative at 80 °C.This green method offers significant advantages in terms of its simplicity,low catalyst loadings,high product yields,and non-toxic nature.The Fe3O4 nanoparticles were characterized by X-ray diffraction,transmission electron microscopy,and Fourier transform infrared spectroscopy. 相似文献
20.
Bidyut Biswas 《Tetrahedron letters》2006,47(24):4019-4021
The synthesis of the allelochemical heliannuol C 1 is described by employing a Bargellini condensation and a Claisen rearrangement to install the gem-dimethyl and vinyl functionalities, respectively. A Dieckmann cyclisation of diester 11 enabled the generation of the benzoxepane ring system enshrined in 1. 相似文献