22515-29-3Relevant academic research and scientific papers
Gold-catalysed oxyarylation of styrenes and mono- and gem-disubstituted olefins facilitated by an iodine(III) oxidant
Ball, Liam T.,Lloyd-Jones, Guy C.,Russell, Christopher A.
supporting information; experimental part, p. 2931 - 2937 (2012/04/23)
1-Hydroxy-1,2-benziodoxol-3(1H)-one (IBA) is an efficient terminal oxidant for gold-catalysed, three-component oxyarylation reactions. The use of this iodine(III) reagent expands the scope of oxyarylation to include styrenes and gem-disubstituted olefins, substrates that are incompatible with the previously reported Selectfluor-based methodology. Diverse arylsilane coupling partners can be employed, and in benzotrifluoride, homocoupling is substantially reduced. In addition, the IBA-derived co-products can be recovered and recycled. The I's have it: The unprecedented use of an iodine(III) reagent as the terminal oxidant for gold-catalysed oxyarylation allows the substrate scope to be significantly expanded; in addition to monosubstituted olefins, styrenes and gem-disubstituted olefins are well tolerated (see scheme). With benzotrifluoride as solvent, unproductive homodimerisation of the arylsilane coupling partner is effectively suppressed. Copyright
A flow microreactor system enables organolithium reactions without protecting alkoxycarbonyl groups
Nagaki, Aiichiro,Kim, Heejin,Moriwaki, Yuya,Matsuo, Chika,Yoshida, Jun-Ichi
supporting information; experimental part, p. 11167 - 11177 (2010/11/04)
A flow microreactor system consisting of micromixers and microtube reactors provides an effective tool for the generation and reactions of aryllithiums bearing an alkoxycarbonyl group at para-, meta-, and ortho-positions. Alkyl p- and m-lithiobenzoates were generated by the I/Li exchange reaction with PhLi. The Br/Li exchange reactions with sBuLi were unsuccessful. Subsequent reactions of the resulting aryllithiums with electrophiles gave the desired products in good yields. On the other hand, alkyl o-lithiobenzoates were successfully generated by the Br/ Li exchange reaction with sBuLi. Subsequent reactions with electrophiles gave the desired products in good yields.
Gold-catalyzed oxidative coupling reactions with aryltrimethylsilanes
Brenzovich Jr., William E.,Brazeau, Jean-Francois,Toste, F. Dean
supporting information; experimental part, p. 4728 - 4731 (2010/12/25)
During continuing studies with a novel oxidative gold oxyarylation reaction, arylsilanes were found to be competent coupling partners, providing further evidence for an intramolecular electrophilic aromatic substitution mechanism. While providing yields complementary to those of the previously described boronic acid methods, the use of trimethylsilanes reduces the observation of homocoupling byproducts and allows for facile intramolecular coupling reactions.
The Diels-Alder Route to Allylsilanes from 1-Trimethylsilylbutadienes
Carter, Martin J.,Fleming, Ian,Percival, Alan
, p. 2415 - 2434 (2007/10/02)
The synthesis and Diels-Alder reactions of 1-trimethylsilylbutadiene (3) and its 3-methyl (17), 3-trimethylsilyloxy (20), 4-methyl (4), and 4-trimethylsilyl (6) derivatives are reported.The silyl group reduces somewhat the rate of the Diels-Alder reactions, and has, if anything, a small 'ortho'-directing effect on the regioselectivity in the reactions of (3) with methyl acylate, methyl propiolate, citraconic anhydride, and 2,6-dimethylbenzoquinone.The other substituent in the dienes (17), (20), and (4) is therefore the major influence on the regioselectivity in the reactions of these dienes with methyl acrylate and methyl propiolate.The products of the Diels-Alder reactions of (3), (17), and (4) are allylsilanes, which undergo clean protodesilylation with acid, and, with the acid and ester derived from the maleic anhydride adduct of (3), undergo epoxidation and sulphenylation reactions giving an allyl alcohol (33) and an allyl sulphide (37), respectively.The adducts from (20) can be hydrolysed to β-silylketones, which can be converted into enones by bromination. 1-Pentamethyldisilylbutadiene (15) is no more reactive and no more regioselective than (3).The 'ortho'-adduct (42) from the reaction of (3) and methyl propiolate aromatises with DDQ to give methyl m-trimethylsilylbenzoate (53) in high yield, in a reaction involving rearrangement of the silyl group, even though a direct dehydrogenation is an available pathway.
