Organopromoted Selectivity-Switchable Synthesis of Polyketones
作者:Jie Liu、Kang-Fei Hu、Jian-Ping Qu、Yan-Biao Kang
DOI:10.1021/acs.orglett.7b02731
日期:2017.10.20
In this work, an organopromoted metal-free pharmaceutical-oriented selectivity-switchable benzylic oxidation was developed, affording mono-, di-, and trioxygenation products, respectively, using oxygen as the oxidant under mild conditions. This process facilitates dioxygenation of 2,6-benzylic positions of heterocycles, which could be inhibited by heterocycle chelation to the metal cocatalysts. Enantiopure
The preparations and some properties of mixed aryl-thienyl oligomers and polymers
作者:Andrew Pelter、Ieuan Jenkins、D.Elfyn Jones
DOI:10.1016/s0040-4020(97)00629-7
日期:1997.7
The syntheses by transition metal coupling reactions of a large number of oligomers constructed from benzene and thiophene rings are described. The first use of arylcadmium chlorides for such coupling reactions is reported. The routes chosen allow for rational variation in the modes of linkage, the substitution and the proportions of the two units. The benzene and thiophene rings are always joined
Stereoretentive Ring-Opening Metathesis Polymerization to Access All-<i>cis</i> Poly(<i>p</i>-phenylenevinylene)s with Living Characteristics
作者:Ting-Wei Hsu、Cheoljae Kim、Quentin Michaudel
DOI:10.1021/jacs.0c04068
日期:2020.7.15
groups. While many synthetic methods afford PPVs with all-trans stereochemistry, very few deliver the all-cis congeners. We report herein a synthesis of all-cis PPVs with living characteristics via stereoretentive ring-openingmetathesis polymerization (ROMP). Exquisite catalyst control allows for the preparation of homopolymers or diblock copolymers with perfect stereoselectivity, narrow dispersities
作者:Benjamin J. Lidster、Dharam R. Kumar、Andrew M. Spring、Chin-Yang Yu、Madeleine Helliwell、James Raftery、Michael L. Turner
DOI:10.1039/c6ob00885b
日期:——
with n-octyl chains have been synthesised from the corresponding dithia[3.3]paracyclophanes using a benzyne induced Stevens rearrangement. The use of 2-(trimethylsilyl)phenyl trifluoromethanesulfonate and tetra-n-butylammonium fluoride as the in situ benzyne source gave significantly improved yields over traditional sources of benzyne and enabled the preparation of n-octyl substituted [2.2]paracyclophane-1
Selective Synthesis of 1,4-Dialkylbenzenes from Terephthalic Acid
作者:Andrea Bramborg、Torsten Linker
DOI:10.1002/adsc.201000322
日期:2010.9.10
Terephthalicacid reacts with alkyl halides under Birch conditions to substituted 1,4‐cyclohexadienes in high yields and good stereoselectivities. Electrophiles containing ester or nitrile groups undergo a surprising fragmentation under the reaction conditions. Subsequent treatment with chlorosulfonic acid proceeds by an interesting tandem decarbonylation/decarboxylation, affording 1,4‐dialkylbenzenes