- Gas permeability of hexaphenylbenzene based polymers of intrinsic microporosity
-
The synthesis and characterization of a series of novel hexaphenylbenzene (HPB) based polymers of intrinsic microporosity (PIM-HPBs) containing methyl, bromine, and nitrile substituents are reported. The successful formation of thin films from these polymers allowed the evaluation of the influence of the substituents on intrinsic microporosity and gas permeability. Analysis by the time-lag method also yielded information about gas diffusion coefficients and, indirectly, the gas solubility. The gas permeability varies as a function of the polarity of the substituents and shows a significant increase after treatment of the samples with methanol, especially for films cast from THF as the solvent. This enhancement, which is mostly due to an increase in the diffusion coefficient, is only partially lost upon aging of the membranes for 5 months. Measurements at different feed pressures confirm the typical dual mode sorption behavior, with increasing diffusivity and decreasing permeability and solubility as a function of the feed pressure.
- Carta, Mariolino,Bernardo, Paola,Clarizia, Gabriele,Jansen, Johannes C.,McKeown, Neil B.
-
-
Read Online
- Palladium-Catalyzed [5 + 2] Heteroannulation of Phenethylamides with 1,3-Dienes to Dopaminergic 3-Benzazepines
-
Phenethyltriflamides react with 1,3-dienes upon treatment with a catalytic amount of Pd(OAc)2 and Cu(OAc)2/O2 as oxidant to afford chemo-, regio- A nd diastereoselectively 2,3,4,5-tetrahydro-1H-benzo[d]azepines (3-benzazepine derivatives) in good to excellent yields. A DFT study of the [5 + 2] heteroannulation suggests a mechanistic pathway starting with formation of the six-membered palladacycle cis-PdX2L2 via a CMD process followed by ??2 coordination and insertion of the 1,3-diene unit in a diastereoselective manner.
- Saá, Carlos,Varela, Jesús A.,Velasco-Rubio, álvaro
-
supporting information
p. 3591 - 3595
(2020/05/01)
-
- A two-step, one pot preparation of amines via acyl succinimides. Synthesis of the calcimimetic agents cinacalcet, NPS R-467, and NPS R-568
-
Abstract A method has been developed for the preparation of amines through a process of coupling acyl succinimides derived from commercially available carboxylic acids with amines to afford the corresponding amides. These amides are then reduced in situ with either diisobutylaluminum hydride or lithium aluminum hydride. The reaction tandem of the coupling reaction followed by the reduction affords the amine in fair to good yields after purification by flash chromatography. This one-pot, two reaction tandem process has been successfully applied to the synthesis of the calcimimetic agents cinacalcet, NPS R-467, and NPS R-568.
- Gooodman, Cassie A.,Janci, Elise Marie,Onwodi, Olivia,Simpson, Chad C.,Hamaker, Christopher G.,Hitchcock, Shawn R.
-
supporting information
p. 4468 - 4471
(2015/06/30)
-
- Hammett analysis of photodecarbonylation in crystalline 1,3-diarylacetones
-
(Chemical Equation Presented) The relative quantum yields and chemical efficiencies of crystalline p,p′-disubstituted 1,3-diphenyl-2-propanones with 4-MeO, 4-Me, 4-F, 4-CF3, and 3,4-diMeO groups were determined by parallel irradiation of polycrystalline samples. Variations in quantum yields that span a factor of 4 are analyzed in terms of the effects of substituents on the stability of the benzylic radical. All solid-state reactions proceeded with 100% chemoselectivity and in >95% chemical yield.
- Resendiz, Marino J. E.,Garcia-Garibay, Miguel A.
-
p. 371 - 374
(2007/10/03)
-
- Synthesis, chemical transformation and antimicrobial activity of a novel class of nitroolefins: 1,3-diaryl-2-nitroprop-1-enes
-
The synthesis of novel, biologically active 1,3-diaryl-2- nitroprop-1-enes (4) is reported. The synthesis involves condensation between aromatic aldehydes (1) and β-aryl nitroethanes (3). The chemical transformation of the nitro group in diaryl nitropropenes to a carbonyl function has resulted in a new route to the synthesis of an α-hydroxy analog (7c) of a naturally occurring 3,3',4,4'-tetramethoxy chalcone. The antimicrobial activity of the 1,3-diaryl-2-nitroprop-1-enes (4a- j) was tested against three gram positive bacteria, two gram negative bacteria and two fungi. These compounds exhibited broad spectrum antimicrobial activity.
- Kodukulla,Trivedi,Vora,Mathur
-
p. 819 - 832
(2007/10/02)
-
- FORMATION OF DERIVATIVES OF β-NAPHTHOLS IN THE REACTION OF HOMOVERATRIC ACID WITH SUBSTITUTED BENZENES IN POLYPHOSPHORIC ESTER; SYNTHESIS OF 6-OXONIABENZANTHRACENE SALTS
-
A new type of reaction was discovered between homoveratric acid and phenyl ethers in polyphosphoric ester, leading to the formation of derivatives of β-naphthols.The polycyclic analogs of 2-benzopyrylium salts obtained on the basis of the β-naphthols, i.e., 6-oxoniabenzanthracenes, do not enter into recyclization reactions.
- Shcherbakova, I. V.,Kuznetsov, E. V.
-
p. 149 - 154
(2007/10/02)
-
- New structural analogs of papaverine: 3 benzyl 6,7 dimethoxy (di and tetrahydro) isoquinolines
-
Syntheses of 3 benzyl 3,4 dihydroisoquinolines by cyclisation of a N acyl α benzylhomoveratrylamine by means of polyphosphoric acid ester, in boiling toluene, gave yields between 60 and 90%. While the hydrogenation of these dihydroisoquinolines to tetrahydroisoquinolines with an alkaline borohydride gave satisfactory result, their dehydrogenation into isoquinolines could not be accomplished. Pharmacological properties of the hydrobromides or hydrochlorides of the bases of the two series of the aforementioned 3 benzylisoquinolines and comparison of their activities with those of papaverine and the analogues 1 and 4 benzylisoquinolines are reported.
- Prudhommeaux,Ernouf,Foussard Blanpin,Viel
-
-