63368-36-5Relevant academic research and scientific papers
Reactions of benzyltriphenylphosphonium salts under photoredox catalysis
Boldt, Andrew M.,Dickinson, Sidney I.,Ramirez, Jonathan R.,Benz-Weeden, Anna M.,Wilson, David S.,Stevenson, Susan M.
supporting information, p. 7810 - 7815 (2021/09/28)
The development of benzyltriphenylphosphonium salts as alkyl radical precursors using photoredox catalysis is described. Depending on substituents, the benzylic radicals may couple to form C-C bonds or abstract a hydrogen atom to form C-H bonds. A natural product, brittonin A, was also synthesized using this method.
Chiral Imidodiphosphoric Acid-Catalyzed Highly Diastereo- and Enantioselective Synthesis of Poly-Substituted 3,4-Dihydro-2 H-pyrans: [4 + 2] Cycloadditions of β,γ-Unsaturated α-Ketoesters and 3-Vinylindoles
Guan, Xu-Kai,Liu, Guo-Feng,An, Dong,Zhang, Heng,Zhang, Suo-Qin
supporting information, p. 5438 - 5442 (2019/08/01)
Imidodiphosphoric acids were employed to catalyze inverse-electron-demand hetero-Diels-Alder reaction of β,γ-unsaturated α-ketoesters and 3-vinylindoles. A series of optically active 3,4-dihydro-2H-pyran derivatives with three contiguous stereogenic centers was synthesized in excellent yields (70-99%), diastereoselectivities (>20:1), and enantioselectivities (73-99%). The resulting indole containing 3,4-dihydro-2H-pyran could be converted to tetrahydropyran derivatives, which appear in several biological active compounds by simple hydrogenation reduction.
Styrylphenylphthalimides as Novel Transrepression-Selective Liver X Receptor (LXR) Modulators
Nomura, Sayaka,Endo-Umeda, Kaori,Aoyama, Atsushi,Makishima, Makoto,Hashimoto, Yuichi,Ishikawa, Minoru
supporting information, p. 902 - 907 (2015/08/24)
Anti-inflammatory effects of liver X receptor (LXR) ligands are thought to be largely due to LXR-mediated transrepression, whereas side effects are caused by activation of LXR-responsive gene expression (transactivation). Therefore, selective LXR modulators that preferentially exhibit transrepression activity should exhibit anti-inflammatory properties with fewer side effects. Here, we synthesized a series of styrylphenylphthalimide analogues and evaluated their structure-activity relationships focusing on LXRs-transactivating-agonistic/antagonistic activities and transrepressional activity. Among the compounds examined, 17l showed potent LXR-transrepressional activity with high selectivity over transactivating activity and did not show characteristic side effects of LXR-transactivating agonists in cells. This representative compound, 17l, was confirmed to have LXR-dependent transrepressional activity and to bind directly to LXRβ. Compound 17l should be useful not only as a chemical tool for studying the biological functions of LXRs transrepression but also as a candidate for a safer agent to treat inflammatory diseases.
Unequivocal experimental evidence for a unified lithium salt-free wittig reaction mechanism for all phosphonium ylide types: Reactions with β-heteroatom-substituted aldehydes are consistently selective for cis-oxaphosphetane-derived products
Byrne, Peter A.,Gilheany, Declan G.
supporting information; experimental part, p. 9225 - 9239 (2012/07/14)
The true course of the lithium salt-free Wittig reaction has long been a contentious issue in organic chemistry. Herein we report an experimental effect that is common to the Wittig reactions of all of the three major phosphonium ylide classes (non-stabilized, semi-stabilized, and stabilized): there is consistently increased selectivity for cis-oxaphosphetane and its derived products (Z-alkene and erythro-β-hydroxyphosphonium salt) in reactions involving aldehydes bearing heteroatom substituents in the β-position. The effect operates with both benzaldehydes and aliphatic aldehydes and is shown not to operate in the absence of the heteroatom substituent on the aldehyde. The discovery of an effect that is common to reactions of all ylide types strongly argues for the operation of a common mechanism in all Li salt-free Wittig reactions. In addition, the results are shown to be most easily explained by the [2+2] cycloaddition mechanism proposed by Vedejs and co-workers as supplemented by Aggarwal, Harvey, and co-workers, thus providing strong confirmatory evidence in support of that mechanism. Notably, a cooperative effect of ortho-substituents in the case of semi-stabilized ylides is confirmed and is accommodated by the cycloaddition mechanism. The effect is also shown to operate in reactions of triphenylphosphine-derived ylides and has previously been observed for reactions under aqueous conditions, thus for the first time providing evidence that kinetic control is in operation in both of these cases.
Aluminium triflate catalysed cyclisation of unsaturated alcohols: novel synthesis of rose oxide and analogues
Coulombel, Lydie,Weiwer, Michel,Dunach, Elisabet
experimental part, p. 5788 - 5795 (2010/03/03)
Aluminium trifluoromethanesulfonate was used as an efficient catalyst for the cycloisomerisation of several unsaturated alcohols into cyclic ethers such as rose oxide and some of its ether analogues.
Stereoselective addition of diphenylphosphine to substituted diphenylethynes: Synthetic, NMR and X-ray crystallographic studies
Bookham, Jonathan L.,Smithies, Darren M.,Wright, Anna,Thornton-Pett, Mark,McFarlane, William
, p. 811 - 818 (2007/10/03)
The base-catalysed addition of diphenylphosphine to the substituted diphenylethynes RC≡CR′ (R = Ph, R′ = Ph, o-tolyl, m-tolyl or 2-biphenyl; R = m-tolyl, R′ = o-tolyl or m-tolyl) yielded Ph2PC(R)=CHR′ and/or Ph2PCH(R)CH(R′)PPh2. Proton, 13C, 13P and two-dimensional rotating frame Overhauser enhancement 1H NMR spectra have been used to determine the stereochemical pathways of the reactions and the stereochemistry of the products. In general the more hindered alkynes undergo monoaddition ultimately to yield phosphinoalkenes with the Ph2P attached to the carbon bearing the least bulky substituent and cis to the olefinic proton, while for the less hindered alkynes the trans isomer is formed initially and this then reacts further to give mesolerythro-diphosphinoalkanes. Bis(o-tolyl)ethyne does not react with Ph2PH under the same conditions. Crystal structures were determined for E- and Z-Ph2P(Ph)C=CHPh and show distortions of interbond angles consistent with the pattern of strain implied by the foregoing reactions. The sulfides of the phosphinoalkenes and the Mo(CO)4 complexes of the diphosphinoalkanes were also prepared and their 1H, 13C and 31P NMR spectra recorded. In several cases the pattern of 13CO NMR signals for the complexes was used unambiguously to determine the stereochemistry of the parent diphosphines.
Synthesis and Photocylization of some 4-(5)Arylethenylimidazoles
Lindberg, Gerd,Stensioe, Karl-Erland,Wahlberg, Kerstin
, p. 679 - 683 (2007/10/02)
The synthesis of eleven 4-(5)arylethenylimidazoles and their separation into cis and trans isomers is described.Ir, uv, nmr, and mass spectrometric data of the compounds are given.The photocyclization of the unsubstituted and p-substituted compounds is reported.
